CA1169061A - .alpha.-OLEFIN COPOLYMERS CONTAINING PENDANT HINDERED AMINE GROUPS - Google Patents

Abstract

Abstract .alpha.-Olefin copolymers having recurring structural units of the formula

Description

The present invention relates to ~-olefin copolymexs containing pendant hindered amine groups which are useful as light and heat stabilizers for organic materials and to stabilized compositions containing said copolymers.

The hindered amine compounds having the 2,2,6,6-tetra-substituted piperidinyl structure have long been known as effective light stabilizers for organic materials and have enjoyed considerable commercial success.

Such hindered aminé light stabilizers are described in detail by H. J. Heller and H. R. Blattmann, Pure and Applied Chemistry, 36, 141-161 (1973~.

It is known from U.S. Patent No. 3,705,166 that mono-meric acrylic acid derivatives which contain at least one piperidinyl group having a sterically hindered nitrogen atom may be used as light stabilizers in organic polymers.
However, these acrylic acid derivatives tend to be too volatile.

In U.S. Patent Nos 4,210,612 and 4,294,949 homopolymeric and certain copolymeric compounds having pendant hindered amine moieties are des~ribed as useful light stabilizers. The '.

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homopolymers are those made by the free radical polymeri~ation of acryloyl or methacryloyl derivatives of compounds containing hindered amine moieties. The copolymers are those made by the free radical copolymerization of the acryloyl or methacry]oyl substituted hindered amine monomers with o.her ethylenically unsaturated monomers such as styrene, an alkyl acrylate, an alkyl methacrylate, acrylonitrile, a maleimide or -N-vinylpyrrolidone. Although ~-olefins are generically disclosed as possible comonomers among a very wide variety of ethylenically unsaturated monomers, ethylene copolymers containing pendant hindered amine moieties are not described nor are their particularly advantayeous properties contempla-ted.

Copolymers of acryloyl or methacryloyl substituted hindered arnine monomers with acryloyl or methacryloyl monomers containino light absorbing moieties such as the benzophenones, benzotriazoles, a-cyanocinnam~tes or benzalmalonates are described in US Patent No. 4,276,401 as being useful liyht stabilizers for organic materials.

This lnvention pertains to ~-olefin copolymers containing pendant hindered amine groups which are useful as light and heat stabilizers for organic materials and to stabilized compositions containing said copolymers.

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~ lore par~icularly, the ~-olefin copolymers of this inverltion have recurring structural units, joined in essentially a random fashion, of the formula I
~CH2C~} 2~ H2~ T (I) wherein T is hydrogen, alkyl of 1 to 18 carbon atoms or mixtbres thereof, Ll is hydrogen or methyl, L2 is hydroxyl, -OCOCH3 or -COOL3, L3 is hydrogen or alkyl of 1 to 6 carbon atoms, E is -COO-, -OCO-, -O- or -CONR-, R is hydrogen, alkyl of 1 to 12 carbon atoms, aralkyl of 7 to 12 carbon atoms, cyclohexyl, hydroxyalkyl of 1 to 6 carbon atoms, alkoxyalkyl of 2 to 10 carbon atoms or dialkylaminoalkyl ~ . .
of 3 to 12 carbon atoms, : ~ 4 -; ' , ~ . '' - , , . , .

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~ :1 6~

G is a gro~p contai.nin~ an N-hetero,~yclic ring of t~e formula Rlz R6. CH3 E~6 ~ ~ ~ CO~ NH ~ ~ CEl2R6 CH3 ~ ~ CH~ - Y.l ~~C ~ N - R5 (III) : ~GCI'2 N C~12~'6 R5 . C~13 CH2R6 .. ~6 -~ ~ .. . .CO - Nl~ ~ C~12R6 X CH 3~ CE13 Rll ~C ~ ~ N- X2 I . .C113 C~12R6 X;7 .
I^ -N ~1 J~R6 R-i1 ~O~LR1 CE13 ~ ¦ CH3 ~ r ; R6CH2 ~ N CH2R6CH3 ~ ~ C113 ~ ~5 R6C}~2 N CH2R6 : . R5 :;
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R-N- Xl - C112CH2-C}l3 ~ C63 ~rC~3 ~ ~ C~l3 R6CH2 N C~12R6 R6C112 N C112R6 in which ~5 is hydrogen, oxyl, Cl-Clg alkyl, C3-Cg alkenyl, C3-C6 alkynyl, C7-C12 aralkyl, -CH2CN, C2-C2ï al~.oxyalXyl, an aliphatic acyl group having 1-~ C
atoms or one of the groups -CH2COOR7 or -COORg, in which R7 is Cl-C12 alkyl, C3-Cg alkenyl, phenyl, C7-Cg araIkyl or cyclohexyl and R8 is Cl-C12 alkyl, phenyl, benzyl or cyclohexyl, and R6 is hydrogen or Cl-C4 alkyl, and Xl is C3-C12 alkylene, -CH2CH20-CH2CH2- or a group of the formula -CH(Rlo)-CH2-(VI), in which Rlo is hydrogen, methyl, ethyl, phenoxymethyl or phenyl, and X2 is a grcup of the formula VI, in which R~o is as c1efin2d above, or a group of the forrnula -CH2-CH(OH)-CH2-(VII), R11 is C1-Clg alkyl or is cyclohexyl, phenyl or benzyl which are unsubstituted ' - . .
.

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or substituted by Cl-C~ alkyl or Cl-C4 alkoxy, Rl is : alkoxy of 1 to 12 carhon atoms, phenoxv, R-N-C113 ~ C~l3 , piperidino or R6C~l2 N C~2R6 ~R2R3 where R2 and R3 are hydrogen, alkyl of 1 to 12 carbon atoms, cyclohexyl or benzyl, R12 is hydrogen or hydroxy, with the proviso that, when R12 is hydroxy, E is -OC0-, a+b+c = 4 to 2600 ~: a = 2 to 2400 b = 0 to 198 c - 2 to 200 a/(a+b~c)= 0.50 to 0.99 :

b~a+b+c~= 0 to 0.49, and c~a-~b+c3= 0.01 to 0.50 ,: ~
~ The ~-ole.~in copolymers of this invention have molecular .
weight in:the .range of 500 to 500,000 as measured by gel permeatlon chromdtography or by viscometl-y of p~lymer solutions or poIymer mell:s.

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The instant ~-olefin copolymers are made up of at least tw~
different rec~lrring structural units while additional different str~ctural units may also be present.

The starting polymeric intermediate is an ~-Glefin copolymer, preferably an ethyle~e copolymer, which may additionally have a second ~olefin component. Preferably only one ~olefin component is present.

In formula I, the first structural unit represents the a ole~in component where T is hydrogen or alkyl of 1 to 18 carbon atoms or mixtures thereof when mixtures of a-olefi~s are used. Preferably T is hydrogen where the ~-o]efin is ethylene.
There is always some of this unit in the copolymer as seen ~y molar ratio values for a/(a+b+c)being a positive number from 0.50 to O.99. On a molar basis at least half of each copolymer of ; this inventio~ is ~-olefin.

The sacond structural unit of formula I represents the polar comonomer with wh1ch the ~~olefin, preferably ethylene, was first polymerized before the pendant hindered amine group i9 attached to the olefin copolymer chain. Such copolymers are olefin, preferably ethylene, copolymers with acrylic acid, lower alkyl acrylates, m.ethacrylic acid, lower alkyl methacrylates and vinyl acetate. When the vlnyl acetate . . .

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copolymer is hydrolyzed, the corresponding vinyl alcohol copolymer is obtained. Thus Ll is hydrogen or methyl, and since acrylic acid and lower alkyl acrylates are preferred, L
is preferably hydrogen.

~ y like token L2 can ~e hydroxy, -OCOCH3 or ~COOL3 where L3 is hydrogen or al~yl of 1 to 6 carbon atoms.
Preferably L2 is -COOL3 where L3 is alkyl of 1 to 6 carbon atoms .

These pendant polar functional groups represen-ted by L2 provide the sites on which, after appropriate esterification, transesterification, amidation or other chemical reaction, a pendant hindered amine moiety may be attached. Preferably essentially all of the existing polar groups in the a-olefin copolymer are r~acted so that very little if any of the original polar groups remain in the final copolymer product containing pendant hindered amine moieties. This is se`en by the molar ratio of b~a-~b+c)which may be and i5 preferably zero.

However, by the judicious choice of amounts of reactants, it is possible to react any desired proportion of -the polar groups L2 to tailor the position and number of pendant hindered amin~ warheads along the polymer chain in the final copolymer product. This allows the preparation of copolymers of :

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specific chemical and physical properties ~or individual end us~
applications. In such cases the molar ratio o~ b/~a+b+c~ is a positive value above zero ranging up to 0.49.

The third structural unit in formula I represents the units to which a hindered amine moiety has been attached. The group 1' i6 -COO-r -OcO-, -0~ or -CONR- which relates directly to the value~ of L2. Preferably E is -COO- or -CONR-.

~ en an alcohol, an amine or an acid cont~ining a hindered amine moiety is r~acted with an olefin copolymer containing pendant L2 groups by standard esterification, transesterifica-tion or amidation procedures, all or a portion of said L2 groups are replaced with groups having the pendant E-G
moieties. The exact nature of G is not critical except that it contains a hindered amine group. Such groups contain an ~I-heterocyclic ring of the formula Rl2 R6 CH3 ~6 ~ CO- ~H ~ ~ CH2R6 C~3 ~ ~ CH3 ~ X~N _ R~ (III~
CH2 N CI12R6 ~
C113 CH2Ro ' P`6 C~13 ~6 ~ CO - ~H ~ ~ CE12~6 C } i 2 n 6 ~ v ) CH3 2 ~

. ~ I
' ' ~ ~9~1 NH - Xl -"~ .

O Xl - , ~ I
~ R6 N

R6CH2 ~ N ~ CH R ~ ~
: R5 R6CH2 N CH2R6 . R5 R-N- Xl - C112C112-C113 \ ~ C~13 or Cll3 ~ ~ C~13 : R5 Rs :
' ln which R is hydrogen, alkyl of 1 to 12 carbon atoms, aralkyl of 7 to 12 carbon atoms, cyclohexyl, hydroxyalkyl of 1 to 6 carbon atoms, alkoxyalkyl of 2 to 10 carbon atoms or dialkylaminoalkyl of 3 to:12 carbon atoms, preferably hydrogen, ~ . ~
~ Rl is alkoxy o 1 to 12 carbon atoms, phenoxy : .~ .
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R~

Cl-i3 ~ 1 Cll3 , piperidino R6Cl~2 N Cll2R6 or NR2R3 where R2 and R3 are hydrogen, alkyl of 1 to 12 carbon atoms, cyclohexyl or benzyl, Rs is hydrogen, oxyl, Cl Cl~, C3-Cg alkerlyl, C3-C6 alkynyl, C7-CI2 aralkyl, CH2CN, C2-C21 alkoxyalkyl, an aliphatic acyl group having 1-4 C atoms or one of the groups -CH2COOR7 or -COOR~
in which R7 is Cl-Cl~ alkyl, C3-C8 alkenyl, ~hen~l C7-C8 aralkyl or cyclohexyl and R8 is Cl-C12 alkyl, phenyl, benzyl or cyclohexyl, and R6 is hydrogen or Cl-C4 alkyl, and Xl is C3-C12 alkylene, CH2CH20CH2CH2- or a group of the ~ormula -CH(Rlo)-CH2-(VI), in which Rlo is hydrogen, metllyl, ethyl, phenoxymethyl or phenyl, and X2 is a group of the :Eormula VI, in which Rlo is as defined above, or a group of ~he formula -CH2-CH(OH)-CH2- (VII), Rll is Cl-Clg alkyl or is cyclohexyl, phenyl or benzyl which are unsubstitllted or substituted by Cl-C4 alkyl or Cl-C4 alkoxy, and ~12 is hydrogen or hydroxy.

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.' G can be preferably a group of the formulae II, III, IV
or V. Most preferably G is a group of the formulae II of IV
where R12 i5 hydrogen.

As Cl-C18 alkyl, R5 is, for example, m~thyl, ethyl, n-propyl, n-butyl, n-pentyl, n-octyl, n-decyl, n-dodecyl or octadecyl. Preferred alkyl groups are those having 1-12 C
atoms, also those having 1-8 C atoms and especially those having 1-4 C atoms and in particular methyl.

As C3-CB alkenyl, R5 is, for example, allyl, 3-methyl-2-butenyl, 2-butenyl, 2-hexenyl or 2-octenyl, especially allyl.

As C3-C6 alkynyl, R5 is, for example propargyl.

As C7-C12 aralkyl, R5 is, for example, benzyl, ~-phenylethyl or 4-tert-butyl-benzyl.

If R5 i5 C2-C21 alkoxyalkyl, the alkyl part can contain 1-3 C atoms and the alkoxy part can consist of 1-18 C atoms, as, for example, in methoxymethyl, ethoxymethyl, 2-methoxy-ethyl, 2-ethoxyethyl 2-n-butoxyethyl, 3-n-butoxypropyl,

2-octoxyethyl or ~-octadecyloxyethyl, .

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1 :?6906:1 preferred compounds are those in which R5 is an alkoxyalkyl group havlng 2-6 C atoms.

As an aliphatic acyl group having 1-4 C atoms, R5 i5, for example, formyl, acetyl, acryloyl or cro~onoyl, e~pecial-ly acetyl.

As Cl-C4 alkyl, R6 is branched or, especially, non-branched alkyl, such as ethyl, n-propyl or n-butyl, but in particu]ar methyl. R6 is preferably hydrogen.

As Cl-C12 alkyl, Rg is, for example, methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-octyl, n-decyl or n dodecyl;
preferably, however, Rg is Cl-C4 alkyl.

As C7-C12 aralkyl, Rg is especially phenylethyl or in particular ~enzyl.

Rlo is phenyl or phenoxymethyl, preferably methyl or ethyl and especially hydrogen.

A~ Cl-C18 alkyl, Rll is, for example, meth~l ethyl r propyl, butyl, hexyl, octyl, dod~cyl or octadecyl. Preferred alkyl groups are those having 1-12 C atoms.

-- 1~ --Rll can also be benzyl, cyclohexyl or phenyl and these can be substituted in the nucle~s by Cl-C4 alkyl, such as methyl, ethyl, propyl or a butyl, or by Cl-C~ alkoxy, such as methoxy, ethoxy, propoxy or n~butoxy.

If R5 is the group -CH2COOR7 or -COOR8, R7 and R8 as Cl-C12 al~yl, are, for example, methyl, ethyl~ isopropyl, n-butyl, isobutyl, t-butyl, isopentyl, n-octyl or n-dodecyl.
Preferably, R7 and R8 are Cl-C~ alkyl. As C3~C8 alkenyl, R7 is, for exampl~, allyl, 2-butenyl or 2-hexenyl. As C7-C8 aralkyl, R7 is, for example, benzyl or ~-phenylethyl~

Prefexably the copolymers of formula I are those where G is a group of the formulae II, III, IV or V, in which R5 is hydrogen, Cl-C12 alkyl~ C3-C5 alkenyl, propargyl, C7-C8 aralkyl, acetyl, or C2-C10 alkoxy-alkyl and R6 is hydrogen or methyl and E is -COO- or -CONR- in which R ~s hydrog~n, Cl-C12 alkyl or benzyl, and Xl is a group of the formula VI, in which Rlo is hydrogen or methyl, and X2 is a group of the foxmulae VI or VII, in which Rlo is as defined above, and Rll is Cl-C12 alkyl or benzyl, and R12 is hydrogen.
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Most preEerred copolymers of for~ula I are those where G is a group of the formulae II or IV, in ~Jhich R5 is hydrogen, C1-C8 alkyl, benzyl or acetyl and R6 is hydrogen or mcthyl and E is -COO- or -CONR-in which R is hydrogen or Cl-Cg alkyl, and X~ is a group of the formulae VI or VII, in which Rlo is hydrogen, methyl or ethyl, and R12 is hydrogen.

Further preferred copolymers of t~e formula I are where G
is a group of the formulae II or IV, in which Rs is hydrogen, Cl--C~ alkyl, benzyl or acetyl and R6 is hydrogen and E is -COO- or -CONR-in which R is hydrogen or Cl-C4 alkyl, and X2 i5 a group of the formulae VI or VII, in which Rlo is hydrogen or methyl, and R12 is hydrogen.

Particularly preferred compounds are ethylene copolymers cf the formula I in which ~ is a group of the formulae II or IV, in which Rs is hydrogen, methyl or acetyl, R~ is hydrogen and E
is -COO- or -CONR-in which R is hydrogen or~Cl-C4 alkyl, and X~ is a group of the formulae VI or VII, in which Rlo is hydrogen, and R12 ~, j i5 hydrogen.

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There is always sorne of this third structural uni~ in the copolymer of tllis i~vention as seen by the molar ratio values for c/~a-~b-~c~being a positive number from 0.01 to 0.50.

Especially prererred are the copolymers where -E-G is -COO

CH3 ~ ~ CH3 CH3 ~ CH3 The molecular weight of the instant olefin copolymers range from about 500 to about 500,000. ~alues of a~b+c = 4 to 2600.

While the instant a-olefin copolymers containing pendant hindered amine groups may range in molecular weight from essentially oligomeric structures wi~h a molecular weight of about 500 to high polymer materials with a molecular weight up to 500,000, the preferred molecular weight range is 5,000 to 100,000 and most preferably is 10,000 to 50,000. These ranges essentially correspond to values of a~b~-c of 40 to 520 and 80 to 260 respectively.
. .

The ~-olefin copolymers such as ethylene/e-thyl acrylate, ethylene/methyl acrylate, ethylene/methyl acry]ate/acrylic acia, ethylene/viny7 acetate, ethyl.ene/vinyl alcohol and the like are - 17 ~

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- ' I :I B9(~ 1 items of commerce with copo].ymers having various molecular weights (melt indices) and weight percents of ethyl acrylate or other comonomers being available.

The free radical polymerization of ethylene or other olefin monomers with various polar comonomers is known in the art and an appropriate diversity of starting olefin copolymer intermediates is thus availableO

Examples of hindered amine alcohols and amines which can be used in the instant invention include 1-(2-hydroxyethyl)-2,2,6,6--tetramethylpiperidine, 1,2,2,6,6-pentamethyl-4-amino-piperidine, l-acetyl-2,2,6,6-tetramethyl-4-aminopiperidine, l-benzyl-2,2,6,6-tetramethyl.-4-aminoplperidine, 1,3,8-triaza-2,4-dioxo-3-(2-hydroxyethyl)-7,7,8,g,9--pentamethylspiro[4.5]-decane, 1,3,8 triaza-2,4-dioxo 3-n-dodecyl-7,7,9,9-tetramethyl-B-(2-hydroxyethyl)-spiro[4.5~decane, 1,3,B-triaza-2,4-dioxo~3-(2-hydroxyethyl)-7,7,g,9-tetramethyl-8-benzylspiro[4.5]decane 1,3,8-triaza-2,4-dioxo-3~n-butyl-7,7,9,9-tetramethyl-8-(2-hy-droxyethyl)spiro~4.5]decane, 1-benzyl-2,2,6,6~tetramethyl-4-(N~n~butyl)aminopiperidine, 1,2,2,6,6~pentamethyl-4-(N-benzyl~-aminopiperidine, 1,2,2,6,6-pentamethyl-4-(N-n-propyl)amino-piperidine, l-allyl-2,2,6,6-tetramethyl-4-hydroxypiperidine and 2,3-dihydroxypropyl)-2,2,6,6-tetramethylpiperidine.

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A typical acid containing a hindered amine aroup is R ~12 COO- lower alkyl C~

3~ ~ J ~ CEI3 ~5 Sueh an aeid ean be attached to an olefin/vinyl alcohol or an olefin/vinyl aeetate eopolymer by standard esterifieation or transesterifieation teehniques.

The aleohols, amines and aeids containing the hindered amine groups are well known in the art.

The piperidinyl derivatives used as reactants are also known eompounds. The preparation o t~le eompounds of the Pormula XI

R6 ~ ~
CE~3 ~ ~ c~3 (XI) R6CH2 N C112~6 ~5 ~ 7B~061 where Y is -O- or -NR- has ~een describecl, for example, in V.S.
Patent No. 4,(114,887 (4-hydroxypiperidines) or in U.S. Patent No. 3,684,765~4-aminopiperidines).

The compc,unds of the formulae XII and XIV

R6. CH3 CO--Nf~ CH2R6 HY Xl_~ ~C ~ - R5 (XII) ~ . . C~13 C~2R6 ':
and ~ R6CI~ C~13~ ~XIV) : 12 Ytt .
can be prepared analogously to the methods described in U.S.
; Patent N~. 3,942i744.

, . .

The preparation of compounds of the formula XIII

CO - Nl~ ~ ~ C~l2R6 R~ 7<N- X 2^ Y 1-C1~3 C~12R6 ' is known, for example, from U.S. Patent No. 3,975,357.

The compounds of the formula XI, XII, XIII and XIV which have different substituent.s in the 2-position and the 6-position of the piperidyl ring can be prepared hy reacting a ketone o~
the formula CH3-CO-CH2-R6 with ammonia. The pyrimidine formed is hydrolysed to an aminoketone of the formula XV, as descrlbed in Helv. Chim. ~cta 30, 114 (1947).
`:

:~ , CE13-C--CH2-cO~cH2 ~6 (XV) :

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~, , , In a second process s~ep, the compounds of the formulaXV
are reacted with ammonia and ke~one CH3-CO-CH2 R6~ as has been described for example,in ~.onatsh. Chemie, B8, (1957) 464 (in ~he indicated formulae, R6 is as defined above). The compounds of the formulae XI and XII in which R5 is hydrogen can be obtained by hydrolysis from the pyrimidine obtained in this way.

The compounds which carry substituents other than hydrogen in the l-position and/or the 4-position are prepared analogouslv to the metho~s described in the literature refer-ences cited above.

While copolymers of this invention are very effective stabilizers for a host of organic substrates subject to light induced detexioration, as are the hindered amines in general, the instant compounds with their surprising resistance to loss from a s abilized composition during high te~perature processing due to volatilization, exudation or sublimation have particular value in stabilizing polymeric substrates which are perforce processed at elevated temperatures.

Th~ copolymers of this invention are particularly useful as stabilizers for the pro~ection of polyolefins, particular-ly polyethylene, polypropylene and polypxopylene fibers.

~ ~ ~906 1 The reasons for this are not certain, but may be related to the high compatibility of the instant olefi.n, particularly ethylene, copolymers in the polyolefin substrates coupled with an enhanced or more efficient utilizat..on of the polar hindered amine stabilizing warheads.

Indeed, it is contemplated that t~,e structure of the inskant ethylene copolymers provides ar, optimum balance between ethylene units for compatibility and separated polar units with pendant hindered amine groups for stabilization efficacy. It appears that the instant copolymers containing a majority of ethylene units along the copolymer bac~.bone with a lesser number of structural units containi.ng pendant hindered amine groups interspersed thereamong allows.for a more effective use of the hindered ami.ne moieties, prevents their undesired agglomeration in the polyolefin substrate and leads to stabilization protection far beyond what would be expected from the same total concentration of stabili.zer having no ethylene components. Indeed, the instant copolymers even with less than 10 mol percent of units having pendant hindered amine groups are very effective light stabilizers in po].yolefin substrates.

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: :~ The copolymers of this invention are effective light `
stabilizers in a wide range of organic polymers. Polymers which :~
~ can be stabilized include:
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1. Polymers which are derived ~rom mono- or diolefins, e.g., polyethylene which can optionally be crosslinked, polypropylene, polyisobutylene, polyme~hylbutene-l, poly-methyl-pentene-l, polyisoprene, polybutadiene~

2. Mixtures of ~he homopolymers cited under 1), for example mixtures of polypropylene and polyethylene, poly-propylene and polybutene-1, polypropylene and polyisobuty-lene.

3. Copolymers of the monomers based on the homopolymers cited under 1), for example ethylene/propylene copolymers, propylene/butene-l copolymers, propylene/isobutylene copoly-mers, ethylene~butene-l copolymers as well as terpolymers of ethylene and propylene with a diene, for example hexadiene, dicyclopentadiene or ethylidene norbornene, and copolymers of ~-olefins, e.g., ethylene with acrylic or methacrylic acid.

4. Polystyrene.

5. Copolymers of styrene and of ~-methylstyrene, for example styrene/butadiene copolymers, styrene/acrylonitrile copolymers, styrene/acrylonitrile~methacrylate copolymers, styrene/acrylonitrile copolymers modified with acrylic ester polymers to provide lmpact strength as well as block copolymerss e.g., styrene/butadiene/styrene block copolymers.

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6. Graft copolymers of styrene, for example the graf~
polymer of styrene ~o polybutadiene, the graft polymer oX
styrene with acrylonitrile to polybutadiene as well as mix-tures thereof with the copolymers cited under 5), commonly referr4d to as acrylonitrile/butadiene/styrene or ABS
plastics.

7. Halogen-containing vinyl polymers, for example polyvinyl chloride, polyvinylidene chloride, polyvinyl fluoride, polychloroprene, chlorinated rubbers, vinyl chloride~vinylidene chloride copolymers, vinyl chloride/vinyl acetate copolymers, vinylidene chloride/vinyl acetate copoly-mers.

8. Polymers which are derived from a,~-unsaturated acids and derivatives thereof, such as polyacrylates and polymetha-crylates, polyacrylic amides and polyacrylonitrile.

9. Polymers which are derived from unsaturated alcohols and amines and from the acyl derivatives thereof or acetals, for example polyvinyl alcohol, polyvinyl acetate, polyvinyl stearate, polyvinyl benzoate, polyvinyl maleate, polyvinyl butyral, polyallyl phthalate, polyallyl melamine and co-polymers thereof with other vinyl compounds, for example ethylene/vinyl acetate copolymers.

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lO. Homopolymers and copolymers which are derived from epoxides, for example polyethylene oxide or the polymers which are derived from bis-glycidyl ethers.

11. Polyacetals, for example polyoxymethylene, as well as polyoxymethylenes which contain ethylene oxide as comonomer.

12. Polyalkylene oxides, for example polyoxyethylene, polypropylene oxide or polybutylene oxide.

13. Polyphenylene oxides.

14. Polyurethane~ and polyureas, such as in urethane coatings~

15. Polycarbonates.

16. Polysulfones.

17. Polyamides and copolyamides which are derived from diamines and dicarboxylic acids and~or from aminocarboxylic acids or the corresponding lactams, for example polyamide 6, polyamide 6/6, polyamide 6/lO, polyamide ll, polyamide 12, poly-m-phenylene-isophthalamide.

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18. Polyesters which are derived from dicarboxylic acidsand dialcohols and/or from hydroxycarboxylic acids or the corresponding lactones, for example polyethylene glycol th~rephthalate, poly-1,4-dimethylol-cyclohexane terephthalate.

19. Cross-linked polymers which are derived from aldehydes on the one han~ and from phenols, ureas and melamine on the other, for example phenol/formaldehyde, urea/form-aldehyde and melamine/formaldehyde resins.

20. Alkyd resins, for example glycerol/phthalic acid resins and mixtures thereof with melamine/formaldehyde resins.

21. Unsaturated polyesters resins which are derived from copolyesters of saturated and unsaturated dicarboxylic acids with polyhydric alcohols as well as from vinyl compounds as cross-linking agents and also the halogen-containing, flame-resistant modifications thereof.

; 22. Natural polymers, for example cellulose, rubber, as well as the chemically modiied homologous d~rivatives ~ thereof, for example cellulose acetates, cellulose propionates ; and cellulose butyrates and the cellulose ethers, for example methyl cellulose.

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I ~ 6nO~ 1 The stabilizing of polyolefins, styrene polymers andpolyamides and of polyurethanes is o particular importance, and the instant copolymers are outstandingly suitable for this. Examples of such polymers are high densi~y and low density polyethylene, polypropylene, ethylene/propylene copolymers, polystyrene, styrene/butadiene/acrylonitrile ter-polymers, mixtures of polyolefins or of styrene polymers, and polyurethanes based on polyethers or polyesters, in the form of lacquers, filaments, films, sheets, films, elastomers or foams.

The copolymeric stabilizers are added to the plastics in a concentration of 0.05 to 5% by weight, calculated relative to the material to be stabilized. Preferably, 0.1 to 2.5% by weight of the copolymers calculated relative to the material to be stabilized, ~rP incorporated into the latter.

Incorporation can be effected after polymerization, for example by mixing the compounds and, if desired, further addltives into the melt by the methods customary in the art, before or during shaping, or by applying the dissolvea or dispersed compounds ~o the polymer, with subsequent evapor-atlon of the solvent if necessary.

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I ~ 6n~6 1 The novel copolymers can also be added to the plastics to be stabilized in the form of a master batch which contains these copolymers, for exa~ple in a concentration of 2.5 to 25% by i weight.

Althou~h the compounds of the invention may be used all above to provide a light stabilizing function, the compounds of this invention are often combined with other stabilizers, even other light stabilizers, in the preparation of stabilized compositions. The stabilizers may be used with phenolic antioxidants, pigments, colorants or dyes, light stabilizers such as hindered amines, metal deactivato s, etc.

In general, the stabilizers of this invention are employed from about O.C5 to about 5~ by weight of the stabilized composition, although this will vary with the particular substrate and application. An advantageous range is from about :
0.1 to about 2.5~.
.
The stabilizers of Formula I may readily be incorporated into the organic polymers by conventional techniques, at any convenient stage prior to the manufacture of shaped articles ; ~thereErom. For example, the stabilizer may be mixed with the ~ ~ ~ polymer in dry powder form, or a suspension or emulsion of the ;~; stabilizer may be mixed with a solution, suspension, or emulsion .~ . ' ~ 29 -, ~ :~

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of the polymer. The stabili~ed polymer compositions of the invention may optionally also contain from about 0.05 to about 5~, preferably from ahout 0.1 to about 2.5~ by weight of various conventional ac1ditives, such as the following, particularly phenolic antioxidants or light-stabilizers, or mixtures thereof.

1. Antioxidants 1.1 Simple 2,6-dialkylphenols, such as, for example, 2,6-di tert.-butyl-4-methylphenol, 2-tert.-butyl-4,6-dimethyl-phenol, 2,6-di-tert.-butyl-4-methoxymethylphenol and 2,6-diocta--decyl-4-methylphenol.

1.2 Derivatives o alkylated hydroquinones, such as for example, 2,5-di-tert.-butyl-hydroquinone, 2,5-di-tert.-amyl-hydroquinone, 2,6-di-tert.-butyl-hydrocluinone, 2,5-di-tert.~
butyl-4-hydroxy-anisole, 3,5-di-tert.-butyl-4-hydroxy-anisole, 3,5-di-tert.-butyl-4-hydroxyphenyl stearate and bis-(3,5-di-tert.-butyl-4-hydroxyphenyl) adipate.
: . ' 1.3. Hydro~yated thiodiphenyl ethers, such as for example, 2,2'-thio-bis-(6-tert.-butyl-4-methylphenol), 2,2'-thio-bis-(4-octylphenol), 4,4'-thio-bis-(*ert.-butyl-3-methylphenol), 4,4'-thio-bis-(3,6-di-sec.-amylphenol), 4,4'-thio~bis-(6-tert.-; - 30 -:
:~ , , :

.
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butyl-2-me-thylphenol) ~n~ 4,4'-bis-(2,6-dimethyl-4-hydroxy-phenyl) disulfide.

1.4 _k~ e-bis~enols, such as, for example, 2,2'-methylene-bis-(6-tert.-butyl-4-methylphenol), 2,2'-methylene-bis-(6-tert.-butyl-4-ethylphenol), 4,4'-methylene-bis-(6-tert.-butyl-2-methylpheno~, 4,4'-methylene-bis-(2,6-di-tert.-butyl-phenol), 2,G-di-(3-tert.-butyl-5-methyl-2-hydroxybenzyl)-4-methylphenol, 2,2'-methylene-bis-[4-methyl-6-(~-methylcyclo-hexyl)-phenol], 1,1-bis(3,5-dimethyl-2~hydroxyphenyl)-butane, 1,l~bis~(5-tert.~buty]~4-hydroxy-2-methylphenyl)-butane, 2,2-bis-(3,5-di-tert.-butyl-4-hydroxyphenyl)-propane, 1,1,3-tris-'5-tert.~butyl~4-hydroxy-2-methylphenyl)-butane, 2,2-bis-¦5-tert.-butyl~4~hydroxy-2-methylphenyl)~4~n-~odecyl-mercapto-butane, 1,1,5,5-tetra-(5-tert.-butyl-4-hydroxy-2-methylphenyl)-pentane and ethylene glycol bis-~3,3-bis-(3-tert.-butyl-4-hydroxyphenyl~-butyrate].

1.5 O-, N~ and S~benzyl compounds, such as for example, 3,5,3',5'~tetra~tert.-butyl-4,4'~dihydroxydibenzyl etiher, octa-decyl 4~hydroxy-3,5~dimethylbenzyl-mercaptoacetate, tris-(3,5-di-tert.-butyl-4-hydroxybellzyl)-amine and bis-(4-tert.~buty]-3-_ ~ hydroxy-2,6-dimethylbenzyl) dithioterephthalate.

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1.6 Hydrox~D nzy]ated malonates, such as for example, dioctadecyl 2,2-bis-(3,5-di-tert.-butyl-2-hydroxybenzyl)-malo-nate, dioctadecyl 2-(3-tert.-butyl-4-hydroxy-5-methy]benzyl)-malonate, di-dodecylmercapto-ethyl 2,2-bis-(3,5-di-tert.-butyl-4-hydroxybenzyl)-malonate and di-[4-(1,1,3,3-te-tramethylbutyl)-phenyl] 2,2~bis-(3,5-di-tert.-butyl-4-hydroxybenzyl)-malonate.

1.7 Hydroxybenzyl-aromatic compounds, such as, for example, 1,3,5-tri-(3,5-di-tert.-butyl-4-hydroxybenzyl) -2,4,6-trimethyl-benzene, 1,4-di-(3,5-di-tert-butyl-4 hydroxy-benzyl)-2,3,5,6-tetramethylberlzene and 2,4,6-tri-(3,5-di-tert.-butyl-4-hydroxy-benzyl)-phenol.

1.8 s-Triazi.ne compounds, such as, for example 2,4-bis-octylmercapto-6-^(3,5-di-tert.-butyl-4-hydroxy-anilino)-s-triazine, 2-octylmercapto-4,6-bis-(3,5--di-tert.-butyl-4-hydroxy anilino)-s triazine, 2-octylmercapto-4,6-bis-(3,5-di-tert.-butyl-4-hydroxyphenoxy)-s-triazine, 2,~,6-tris-(3,5-di-tert.-butyl-4-hydroxyphenoxy)-s-triazine, 2,4,6-tris-(3,5-di-tert.-butyl-4-hydroxphenylethyl)-s-triazine and 1,3,5-tris-(3,5-di-tert.-butyl-4-hydroxybenzyl) isocyanurate.

1.9 A~mides of ~-~3,5-di-tert.-butyl-4-hydroxyphenyl)-pro-pionic acids, such as, for example 1,3,5--tris-(3,5 -di-ter!.-butyl-4 hydroxyphenyl-propionyl)-hexahydro-s-triazine and ~ ~ ~9~ ~

N,N'-di-~,5-di-ter-t.-butyl-4-hydroxyph~nyl-propionyl)-hexa-methylenediamine, N,N'-bis-~-(3,5-di-t-butyl-4-hydroxy~henyl)-propionyl-hydrazine.

1.10 Esters of ~-(3,5-di-tert.-bu1yl-4-hyclroxy~_nyl)-pro-pionic acid with monohydric or polyhydric alcohols, such as Eor example, with methanol, ethanol, oc-tadecanol, 1,6-hexanediol;.
l,9-nonanediol, ethylene glycol, 1,2-propane-diol, diethylene glycol, thiodiethylene glycol t neopentylglycol, pentaerythritol, 3-thiaundecanol, 3-thia-pentadecanol, trimethylhexanediol, trimethylolethane, trimethylolpropane, tris-hydroxyethyl isocyanurate and 4-hydroxymethyl-1-phospha-~,6,7-trioxabicyclo-~2.2.2]octane.

1.11 Esters o~ ~-(5-tert.-butyl-4-~y~droxy-3-methylphenyl)-propionic acid with monohydric or polyhydric alcohols, such as for example, with methanol, ethanol, octadecanol, 1,6-hexanediol, 1-9-nonanediol, ethylene g]ycol, 1,2-propanediol, di~ ethylene glycol, thiodiethylene glycol, neopentylglycol, pentaerythritol, 3-thia-undecanol, 3-thia-pentadecanol, trimethylhexanediol, trimethylolethane, trimethylolpropane, tr s-hydroxyethvl isocyanurate and 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo[2.2.2.~octane.

.~

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, 1.12 ~sters of 3,5-cli-tert.-buty]-4-hy~droxy~henylacetic acid with monohydric or polyhydric alcohols, such as for exarnple, with ~ethanol, eth~nol, octadecanol, 1,6-hexancliol, l,9-nonanediol, ethylene glycol, 1,2-propanediol, diethy]ene g]ycol, thiodiethylene glycol, neopentylglycol, pentaerythri-tol, 3-thia-undecanol, 3-thia-pentadecanol, trimethylhexanediol, trimethylolethane~ trimethylolpropane, tris-hydroxyethyl .isocyanurate and 4-hydroxymethyl-1-phospha-2,6,7-trioxabicyclo-C2.2.2]-octane, especially the tetrakis ester of pentaerythritolO

1.13 Ben~y_ph sphonates, such as, for example, dimethyl 3,5 di-tert.-butyl-4-hydroxybenzylphosphonate, diethyl 3,5-di-tert.-bu~yl-4-hydroxybenzylphosphonate, dioc~adecyl 3,5-di-tert.-butyl-4-hydroxybenzylphosphonate and dioctadecyl 5-tert.-butyl-4-hydroxy-3-methylbenzylphosphonate.

2. Light-stabilizers 2.1 Esters of optionall~ substituted benzoic acids, e.g., 3j5-di-tert.-butyl-4-hydroxybenzoic acid, 2,4-di-tert.-butyl-phenyl ester or -octadecyl ester or 2-methyl-4,6-di-~ert.-butyl-phenyl ester.

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9 ~ ~ 1 2.2 Sterl _ ly hindered amines e.g., 4-benzoyl-2,2,6,6-tetrame-thylpiEeridine, 4-stearyloxy-2,2,6,6-tetramethyl-piperidine, bis-(2,2,6,6-tetramethylpiperidyl) sebacate, bis-(1,2,2,6,6-pertamethylpiperidyl) sebacate, bis-(1,2,2,6,6-pentamethylpiEeridyl) 2-n-butyl-2-(2-hydroxy-3,5-di-tert-butyl-benzyl)malonate or 3-n-octyl-7,7,9,9-tetra-methyl-1,3,8-triazaspiro[4.5]decane-2,4-dione.

2.3 Oxalic acid diamides, eOg., 4,4'-di-octyloxy-oxani-lide, 2,2'-di-octyIoxy-5,5'-di-tert.butyl-oxanilide, 2,2'-di-dodecycloxy-5,5'-di tert.-butyl-oxanilide, 2-ethoxy-2'-ethyl-oxanilide, N,N'-bis-(3-dimethvl-amlnopropyl)-oxala~ide, 2-ethoxy-5-tert.-butyl-2'-ethyl-oxanilide and the mixture thereof with 2-ethoxy-2'-ethyl-5,4'-di-tert.-kutyl-oxanilide, or mixture of ortho- and para-methoxy- as well as of o- and p-ethoxy-di-substituted oxanilides.

~' 3. Metal deactivators, e.g., oxanilide, isophthalic acid , dihydrazide, sebacic acid-bis-phenylhydrazide, bis-benzyli-dene-oxalic acid dihydrazide, N,N'-diacetal-adipic acid dihydrazide, N,N'-bis-salicyloyl-oxalic acid dihydrazide, N,N'-bis-salicyloylhydrazine, N,N'-bis-(3,5~di-tert.-butyl-4-hydroxy-phenyIpropionyl)-hydxazine, N-salicyloyl-N'-salicylalhydrazine, ~:
3-salicyloyl-amino-1,2,4-triazole or N,N'-bis-salicyloyl-thio-propionic acid dihydra2ide.

,~ .

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4. Basic co-stabili.~ers, e.g., alkali metal salts and alkali.ne-earth metal salts of hiaher fatty acids, for example Ca-steara~e, Z~-stearate, Mg-behenate, Na-ricinoleate or K-palmitate.

5. Nucleation agents, e.g., 4-tert.-butylbenzoic acid, adipic acid or diphenylacetic acid.

6. Phos~hites and phosphonites, such as, for example, triphenyl phosphite, diphenylalkyl phosphites, phenyldialkyl phosphites, tri-(nonyl-phenyl) phosphite, trilauryl phosphite, trioctadecyl phosphite and 3,9-isodecyloxy-2,4,8,10-tetraoxa-3,9-diphospha~[5.5~-undecane and tetra(2,4-di-tert-butyl~henyl) diphenylene-4,4'-bis(phosphonite).

Other additives that can be incorporated in the stabilized compositions are thiosynergists such as dilauryl thiodiproprion-^~
ate, lubricants such as stearyl alcohol, fi].lers, asbestos, kaolin, talc, glass fibers, pigments, optical brig~teners, flameproofing agents and antistatic agents.

While the instant copolymers containing pendant hindered a~ine moieties G are particularly useful as stabiliz~ers for polymeric substrates, it is also contemplated that said copolymers would provide dyesites for the subsequent dyeing of ~; .

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.he stabilized polymer with acid dyes. This wou]d be rnost beneficial in the dyeing of polyolefins such as poly~ropylene by the inclusion of the hindered amine ba;ic s'te into polyo]efin fiber.

The following examples are presented for the purpose of illustration only and are not to be construed to limit the nature or scope of the instant invention in a~.y manner whatsoever.

:
Rthylene/2,2,6,6-Tetramethylp~e_~ yl Acrylate Copolymer In a 500-ml 3-necked round-bottomed flask fitted with a stirrer, reflux condenser, thermometer, nitrogen inlet tube and an oil bath was placed a mixture of 14.5 grams of ethylene/ethyl acrylate copolymer (77/23) with a number average molecular weiyht of 28,000 with an ethyl acrylate content of 23% by weight (= 0.033 mole of ethyl acrylate~, 15.7 grams (0.1 mole) 2,2,6,6-tetramethylpiperidin~4-ol and 0.3 gram o tetrabutyl titanate. The mixture was heated at 175C under a nitrogen atmosphere for 20 hours with gentle stirriny.

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A quan-titative amoullt (0.033 mole 1.52 grams) of ethano]
was liberated in the transesterificati()n reaction and ~1as collected ln 2 suitable trap cooled by an acetone-dry ice bath.

The resulting copolymer product was then dissolved in 150 ml of anhydrous toluene. The toluene solution was then added dropwise into an excess of anhydrous hexane to precipitate t~e copolymer. The copolymer was isolated by filtra-tion and then suspended in refluxing acetone to extrcct any unreacted 2,2,6,6-tetramethylpiperidin-4-ol. The extracted and purified desired copolymer was isolated by filtration and dried at 50C/0.2 mm for 7 hours. The desired copolymer was obtained in a yield of 15.5 grams (95~).

Analysis:
Calculated (~) C: 79.02; H: 12.55; N: 2.57.
Found (%) C: 79~94; H: 12.01; N: 2.08.

EXAMPLE la When the reaction of Example 1 was carried out using only 3.15 grams (0.02 mole) of 2,2,6,6-tetramethylpiperidin-4-ol, that is an 0.6 molar equivalent of 2,2,6,6-tetramethylpiperidin-4-ol rather than a 3 molar equivalent amount per pendant ester group in the ethylene/ethyl .:

.

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acrylate (77/23) copolymer, a product was obtained in ~hich approximately half the pendant ethyl ester groups were replaced by hindered amine moieties. The product con-tained l.12 nltrogen .

Ethylene/2,2,6,6 Tetramethylpiperidin-~-yl Acrylate Copolymer The above-named copolymer was prepared using the general procedure of Example 1 by the use of an equivalent amount of an ethylene/ethyl acrylate (82/18) copolymer with a number average molecular weight of 33,000 with an ethyl acrylate content of 18t;
by weight.

~ ~ .
Analysis:
Calculated (%) C: 80.10; H: 13.02; N: 2.10.
:~: Found (~ C: 80.38; H: 12.85; N: 1.78.

X~MPLE 3 ~ .
Ethylene/2,2,6,6-Tetramethylpiperidin-4 yl Acrylate Copolymer . ~ .
. The above-named copo]ymer was prepared using the ~eneral : procedure of Example 1 by the use of an equivalent amount of an ~ ethylene/ethyl acrylate (61/39) copolymer with a n~mber average : ~ :

~ 3g -, 3 ~ 6 :~

molecular weicht of 28,000 with an ethyl acrylate content of 39%
by weight.

Analysis:
Calculated (%) C: 75.56; H: 11.86; N: 3.83.
Found (%) C: 74.84; H: 11.38; N: 3.22.

Ethylene/1,2,2,6,6-Pentamethylpiperidin-4-yl Acrylate Copolymer The above-named copoiymer was prepared by the general procedure of Example 1 by sub~tituting for the 2,2,6,6-tetra-methylpiperidin-4-ol an equivalent amoullt of 1,2,2,6,6-penta-methylpiperidin-4-ol, and reacting with an ~;~ ethylene/ethyl acrylate copolymer (77/23).
~ .
Analysis: .
Calculated (%) C: 79.06; H: 12.56; N: 2.550 Found (%) C: 79.07; H: 12.36; N: 2.32 ',~

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EXAMPLE 5_ Ethylene/1-(2-Acryloyloxyethyl)-3,3,5,5-tetramethyl-~pera in -2,6-dione Copolymer The above-named copolymer was prepared by the general procedure of Example 1 by substituting for the 2,2,6,6-tetramethylpiperidin-4-ol an equivalent amount of 1-~2-hydro~yethyl)-3,3,5,5-tetramethylpiperazine-2,6-dione. The reaction was run at 210C.

Analysis:
Calculated (%) C: 75.46; H: 11.86f N: 3.86.
Found (~) C: 75.43; H: 11.48; N: 3.50.

~' Ethylene/1,2,2,6,6-Pentamethylpiperidin-4-yl Acrylate Copolymer : ' :
To a 1000 ml round bottomed flasX fitted as was the flask in Exal~ple 1 was charged 46.2 grams of 1,2,2,6,6-pentamethyl-piperidin-4-ol and 50 grams of ethylene/ethyl acrylate (82/18) copolymer havin~ a num~er average molecular weight of 33,000, an ethyl acrylate content of 18% by weight, and a melt flow rate of 6g/10 min. (ASTM D1238, cond. E~.

I :~ 69~ ~

The mixt~re was heated under a nitrogen atmosphere at 180C
for 30 minutes till essentially all the polymer pellets were melted. The hot melt was gently s-tirred to give a hot homogeneous mix to which 1 gram of tetrabutyl titanate was added.

The reaction temperature was raised to 210C and aliquot samples of product were taken at 4-hour intervals. After 12 hours, the temperature was lowered to 120C and 500 ml of toluene were added 610wly with stirring. The resulting toluene solution was then added slowly into 2000 ml of methanol with vigorous stirring to precipitate the desired product. The precipitate was suspended in the methanol with stirring for another five hours before isolating by filtration. The isolated product was washed with methanol and dried at room temperature/0.1 mm for 1 hour and then at 80C/0.1 mm for two hours. The copolymer was obtained as free flowing wh~te granules readily soluble in hot toluene or hot xylene.

Analysis:
Calculated (%) C: 80.22; H: 13.05; N: 2.05.
Found (%) C: 80.23, H: 13.07 N: 1.96.

:

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EXA~PLE 7 Ethylene/2,2,6,6-Tetramethylpiperidin~ _A~y~ate Copo_y~er The above-named copolymer was prepared by the general procedure of Example 6 by substitu-ting for 1,2,2,6,6-penta-methylpiperidin-4-ol an equivalent amount of 2,2,6,6-tetra-methylpiperidin-4-ol. The product had a melt flow rate of 8g/10 min. (ASTM D1238, cond. E).

Analysis:
Calculated (%) C: 80.10; H: 13.02 N: 2.15.
Found (%) C: 80.85; H: 12.53; N: 1.98.

Tbe copolymer was obtained as free flowing white granules which were soluble in hot xylene or hot toluene.

~, .
` ~ EXAMPLE 8 . . .

Ethylene/2,2,6,6~Tetramethylpiperidin~4~yl- Acrylate Copolymer ~ Using the procedure of Example 7, but with an ;~ ethylene/ethyl acrylate copolymer having a number average molecular weight of 33,600 and an ethyl acrylate content of 18 - 43 ~

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by weight, th~ above-na~,ed copolymer was obtained as whi~e ruhhery granu~es. The co~olymer was readily soluble in hot xylene or hot to]uene.

Ethylene/2,2,6,6-Tetramethylpiperidin-4-yl~crylate Copolymer To a 500-ml resin kettle equipped with a stirrer and thermometer was charged 86.1 grams of a granulated copolymer of ethylene/methyl acrylate (80/20) havins a melt index of 2 (ASTM
method D 1238, cond. E). The copolymer contained 17.2 grams (0.2 moles) of methyl acrylate. To the pclymer was added 80 ml of xylene and 39.3 grams (0.25 moles) of 2,2,6,6-tetra~ethylpiperidin-4-ol. The reaction mixture was heated for 30 minutes at 150C and then 0.23 gram (0.01 mole) of lithium amide catalyst was added. The mixture was heated for a further 8 hours at 145-150C with stirring while a slow nitrogen sw~ep stream was passed through the systemO The catalyst was then deactivated by the addition of one ml of acetic acid followed by stirring for two hours at 145C.

, The viscous liquid mass was poured onto aluminum sheets and cooled. The now solidified product was cut into small pieces and ground in a Wiley mill together with dry ice. The ground .

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product (160 gralns) was washed with a lotal of 1000 ml of methanol in six portions and then driec at room temperature.
The procluc-t contained 2.02~ nitrogen (calculated, for complete replacement of ~ethyl ester by hinderec amine, 2.52~ ni~rogen).

NMR spectra indicated 20~ residual methyl ester groups in the product. Transesterification was thus 80~ complete.
Evaporation of the methanol washings resulted in a quantitative recovery of the remaining unreacted 2,2,6,6-tetramethyl-piperidin-4-ol (13.7 grams, 0.087 moles).

Copolymer with Pendant Amide Groups A mixture of 15 grams of an ethylene/ethyl acrylate (82/18) copolymer, 36 grams of 4-(y-aminopropylamino)-2,2,6,6-tetra-methylpiperidine and 13 grams of ground potassium fluoride was heated at 200C for 25 hours. The reaction mixture was then diluted with 50 ml of xylene and poured .into 1000 ml of methanol. The resulting precipitate was filtered, washed thoroughly with ethanol and water, and then dried. The nitrogen content o 2.29~ indicated that approximately 40~ of the pendant ethyl ester groups had been converted into the hindered amine amide groups.

1 ~ &~a~ ~

EXAMPLF.S 11-16 The follo~ing polymers were obtained by transesterification of an ethylene/ethyl acrylate (82/18) copolymer using the alcohols i.ndicated in the table below. The transesterification reactions were carried out in the presence of tetrabutyl titanate as catalyst at 150-200C.

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Po 1 ymer Example Pol~nler %N ~N
No. Alcohol M~ calcd found C~13 ~3 ~(CH2)6- NH- C NH 455()03.65 3.29 ~CH3 o CH3 ~ CH3 12HOCH2CH~- N NH 430003.86 3.32 7~CH3 13 HOCE-12CH2- N, ~ NH 440003.79 3.l9 ~ H3 : CH3 / CH
: 14 HOCH2CH20CH~CH2-NH ~ 450003.71 2.95 . CH3 : ~ CH3 15HOCH2CH2OCE~2cH2-~ ~ N-CH3 46500 3.58 3.08 CH3 ~ CH3 : :

~:~ ~ H3 16HOCH2C}l2- ~ ~ NH 45,500 3.65 3.05 C4Hg ~
~CH3 . 47 -1~, :; -o ~ ~

Accelerated UV Li~ht Exposure Testi g Polypropylene powder (Hercules Profax~ 6401) was thoroughly blended with 0.2% by weight of the antioxidant, di(n-octadecyl) 3,5-di-tert-butyl-4-hydroxybenzylphosphonate, which prevents oxidative degradation of polypropylene during processing and with 0.5% of a light stabilizer being tested. The blended materials were then milled on a two-roll mill at 182C for 5 minutes after which time the stabilized polypropylene was sheeted ~rom the mill and allowed to cool.
The milled polypropylene sheets were Cllt into pieces and processed for 3 minutes on a hydraul,ic press at 220C and 175 psi (12.3 Kg/cm ) pressure. The resulting sheet of 5 mil (0.127 mm) thickness was water cooled in the press.
The 5 mil (0.127 mm) film was tested in a fluorescent sunlight black light environment with the development of carbonyl absorption in the in~rared spectrum at the 5.85 micron wavelength being the measure of stabilization protection a~forded by the stabilizers present in the polypropylene. Failure was taken as the hours required to cause the carbonyl absorption to reach a value of 0.5. Such a value correlates with XTrade Mark :`
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the reduction of physical properties of the polypropylene pellicle to unacceptable ].evels and is proportional to the amount of degradation caused by the ultraviolet light exposure.
The results are set out in Table A.
TABLE A

Polypropylene plus Fluorescent Sunlight 0.2% by weight anti- Black Light Test Hours oxidant* plus O . 5~ to Failure by weight light (0.5 Carbonyl Absorption) stabilizer of Example No.

No light stabilizer 560 16~0 * antioxidant is ditn-octadecyl) 3,5-di-tert-butyl-4-hydroxy-benzyl~hosFhonate.

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Using the general procedure of Example 17, linear low density polyethylene (Dowiex 2047, initial melt index 3.4g/10 min) which contained 0.015~ by weight o~ pentaerythrityl tetrakis-(3,5-cli-tert-butyl-4-hydroxyhydrocinnamate) as antioxidant was blended with the instant ethylene copolymer light stabilizers and then compression molded into 5 mil (0.127 mm) film test samples.

These samples were tested in a carbon arc Weather-O-meter with water spray attachment to simulate rainfall and in the fluorescent sunlight black light apparatus with the develop-ment of carbonyl absorption as measured at the 5.85 micron wavelength in the infrared spectrum taken to indicate the degree of stabilization protection afforded by said light stabilizers.
The results are set forth in Table B.

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TABL~ B
.

Linear Polyethylene Ho;~rs to Failure plus 0.015~ by weiaht (0.5 Carbon~_Absorption?
antioxidant* plus (% by ~luorescent weight) light stabilizer Carbon Arc Sunlight BlacX
of Example No. WeatherOmeter Liaht , .
~o light stabilizer 379 1089 7 (0.25) 1881 >4551 7 (0.50) 1961 >5122 7 (1.0~) 2036 >5122 6 (0.25) 1831 >5122 6 (0.50) 1~33 >5122 6 (1.00) 1814 >5122 * antioxidant is pentaerythrityl tetrakis (3,5-di-tert~butyl-4-hydroxyhydrocinnamate) These data show the outstanding e~fectiveness of the instant ethylene copolymers as light stabilizers even at very low concentrations (0.25~ by weight) in linear polyethylene.

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~ :~ 6~0~ 1 There was no exudation of the instant ethylene copolymer light stabilizers from linear polyethylene after storage at ambient temperatures for 1000 hours and for 3000 hours.

Polypropylene (Hercules Profax 6501~) containing 0.1% by weight of calcium stearate, but no antioxidant, was blended with the instant ethylene copolymer light s~abilizers. The mixture was pelletized and extruded at 450F (232C) into 4 inch (10.2 cm) tape with a thickness of 5 mil (0.127 mm). The tape was cut into 1/4 inch (6.4 mm) wide strips which were then stretched by a 6:1 ratio over ~odet rolls at a temperature of 225F (107C) to give a stretched film tape of 2 mil (o.o508 mm) thickness.
The tape was sub~ected to long term heat aging at 125C
by storing in an oven at 125C with the hours to failure being taken as the time (hours) required for the elongation value to ; fall to 50% of the initial value.

~Trade Mark ~: :
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Separate samples were also subjected to the carbon arc WeatherOmeter with the same measure of hours to failure being taken.
The results are given in Table C.

TABLE C
Polyethylene Hours -to ~lailure plus 0.1% by weight (50% Retention of Elongation) light stabilizer Carbon Arc Long Term Heat of Example No. WeatherOmeter Aging (125C) ._ no light stabilizer 344 69 These data show that the instant ethylene copolymers are very effective light and heat stabilizers for polypropylene.
EXAMPLE ?
.
Using the general procedure of Example 19, polypropylene 2 mil (0.o508 mm) tape made with polypropylene (Hercules, Profax 6501~) containing 0.1% by weight of calcium stearate, 0.05% by ~; weight of the an-tioxidant, 2,6-di-tert-butyl-p-cresol, and 0.1%
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of an ethylene copolymer of this invention was subjected to lon3 term heat aging a~ 125C with hours to failure being recorded when only 50 of the original elongation value of the tape was reached. The results are given in Table D.

TABLE D

~: PolypropyleneHours to Failure plus 0.05% by weight(SO~ Retention of Elongation antioxidant* and 0.1% by Long Term Heat weight light stabilizer_ Aging at 125C
of Example no light stabilizer 43 8 54~

; * 2,6-di-tert-butyl-p-cresol Again the instant ethylene copolymers exhibit excellent heat stabilization effect~ for polypropylene.

:

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Using the general procedure of Ex~lmple 20, 0.1% of the i.nstant stabilizer was incorporated in~:o polypropylene and exposed in a carbon arc Weather-Ometer. The time required for the elongation value to fall to 50% of the original ~alue was determined. The results are given on ~'able E.

Table E

Polypropylene plus 0.1% by ~ours to Fa;lure weight of light (50~ Retention o~ Elongation) Stabilizer of Example No. _Carbon Arc Weather-Ometer no stabilizer 317 11 , 61 9 : 15 1190 16 . 1166 ~ .

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Example 22 .

Ethylene/Viny]. 1,2,2,6,6-Pentamethylpiperidine-4-carboxylate Copolym r The above-named copolymer is prepared by the general procedure of Example 1 by substituting for the 2,2,6,6-tetramethylpiperidin-4-ol an equivalent amount of methy:L
1,2,2,6,6-pentamethylpiperidine-4-carboxylate and reacting with an ethylene/vinyl acetate copolymer t75/25~.

Example 23 The copolymer of Example 22 is an effe~tive light and heat stabilizer for polypropylene.
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Claims (20)

WHAT IS CLAIMED IS:

1. An .alpha.-olefin copolymer having recurring structural units, joined in essentially a random fashion, of the formula I

(I) wherein T is hydrogen, alkyl of 1 to 18 carbon atoms or mixtures thereof, L1 is hydrogen or methyl, L2 is hydroxyl, -OCOCH3 or -COOL3, L3 is hydrogen or alkyl of 1 to 6 carbon atoms, E is -COO-, -OCO-, -O- or -CONR-, R is hydrogen, alkyl of 1 to 12 carbon atoms, aralkyl of 7 to 12 carbon atoms, cyclohexyl, hydroxyalkyl of 1 to 6 carbon atoms, alkoxyalkyl of 2 to 10 carbon atoms or dialkylaminoalkyl of 3 to 12 carbon atoms, G is a group containing an N-heterocyclic ring of the formula (II), (III) (IV) (V) or in which R5 is hydrogen, oxyl, C1-C18 alkyl, C3-C8 alkenyl, C3-C6 alkynyl, C7-C12 aralkyl, -CH2CN, C2-C21 alkoxyalkyl, an aliphatic acyl group having 1-4 C atoms or one of the groups -CH2COOR7 or -COOR8 in which R7 is C1-C12 alkyl, C3-C8 alkenyl, phenyl, C7-C8 aralkyl or cyclohexyl, and R8 is C1-C12 alkyl, phenyl, benzyl or cyclohexyl, and R6 is hydrogen or C1-C4 alkyl and X1 is C3-C12 alkylene, -CH2CH2OCH2CH2- or a group of the formula -CH(R10)-CH2- (VI), in which R10 is hydrogen, methyl, ethyl, phenoxymethyl or phenyl, and X2 is a group of the formula VI, in which R10 is as defined above, or a group of the formula -CH2-CH(OH)-CH2- (VII), R11 is C1-C18 alkyl or is cyclohexyl, phenyl or benzyl which are unsubstituted or substituted by C1-C4 alkyl or C1-C4 alkoxy, R1 is alkoxy of 1 to 12 carbon atoms, phenoxy, , piperidino or NR2R3 where R2 and R3 are hydrogen, alkyl of 1 to 12 carbon atoms, cyclohexyl or benzyl, R12 is hydrogen or hydroxyl, with the proviso that, when R12 is hydroxyl, E is -OCO-, a + b + c = 4 to 2600 a = 2 to 2400 b = 0 to 198 c = 2 to 200 a/(a + b + c)= 0.50 to 0.99 b/(a + b + c)= 0 to 0.49, and c/(a + b + c)= 0.01 to 0.50

2. A copolymer according to claim 1 wherein T is hydrogen.

3. A copolymer according to claim 2 wherein b is zero.

4. A copolymer according to claim 2 wherein L1 is hydrogen.

5. A copolymer according to claim 2 wherein L2 is -COOL3, and L3 is alkyl of 1 to 6 carbon atoms.

6. A copolymer according to claim 2 wherein E is -COO- or -CONR-.

7. A copolymer according to claim 2 wherein -E-G is

8. A copolymer according to claim 2 which is ethylene/1,2,2,6,6-tetramethylpiperidin-4-y1 acrylate.

9. A copolymer according to claim 2 which is ethylene/1,2,2,6,6-pentamethylpiperidin-4-y1 acrylate.

10. A copolymer according to claim 2 which is ethylene/1-(2-acryloyloxyethyl)- 3,3,5,5- tetramethylpiperazine-2,6-dione.

11. A composition of matter comprising, an organic material subject to light-induced deterioration stabilized with from 0.0?
to 5% by weight of a copolymer according to claim 1.

12. A composition according to claim 11 in which the organic material is a polyolefin.

13. A composition according to claim 12 wherein the polyolefin is polyethylene,.

14. A composition according to claim 12 wherein the polyolefin is polypropylene.

15. A composition according to claim 11 wherein the copolymer is ethylene/2,2,6,6-tetramethylpiperidin-4-yl acrylate.

16. A method of stabilizing an organic material subject to light-induced deterioration which comprises incorporating in said material from 0.05 to 5% by weight of said material of a copolymer according to claim 1.

17. A method according to claim 16 in which the organic material is a polyolefin.

18. A method according to claim 17 wherein the polyolefin is polyethylene.

19. A method according to claim 17 wherein the polyolefin is polypropylene.

20. A method according to claim 16 wherein the copolymer is ethylene/2,2,6,6-tetramethylpiperidin-4-yl acrylate.