DE1494865A1 - Sizing compounds for fibers containing silica - Google Patents

Description

Patent attorneys Dr-lng. HANS RUSCHKE DipWng. HEiNZ AGULAR

8 Make 27, Pi.r ~ nau.rSlr. 2 1494355 ¹ ^ MdI 1965

The Dow Chemical Company, Midland, Michigan, V.St.A.

Sizing compounds for fibers containing icic acid

The present invention relates to a mass and a Process for sizing glass fibers. In particular, the invention relates to the coating of glass fibers with a film-forming mixture of an acrylamide polymer and a non-ionic water-soluble cellulose ether.

The term "size" is used herein to refer to an adhesive coating for glass fibers. Finishing is at Glass fibers applied to their processability in the production of glass textiles, glass insulation and the like to improve composite structures made of glass fibers.

So far, most sizes for glass fibers have been based on starch. It is known to those skilled in the art that starchy Masses support fungal growth and, as a result, such sizes suffer relatively rapid damage with accompanying discoloration.

It has now been found that two polymeric substances which normally have little or no active

909850/0169

viability as a sizing agent for glass fibers due to the fact that every polymeric substance does not itself effectively adheres to the glass, when mixed with each other in a common aqueous medium, the basis for a result in an excellent size for glass fibers. This new size actually has excellent properties in terms of flexibility and adhesion to glass fibers.

The sizing composition according to the invention for silicic acid-containing Fibers consists of an aqueous solution or contains an aqueous solution which is 0.2 to 20% by weight? » of a mixture from one part by weight of a water-soluble acrylamide polymer and 0.1 to 10 parts by weight of a non-ionic, contains water-soluble cellulose ether. The sizing composition according to the invention contains 1 part of an acrylamide polymer and 0.1 to 10 parts, preferably 1 to 5 parts, of a non-ionic, water-soluble cellulose ether. the Sizing compound is applied to the silica-containing fibers in the form of a practically aqueous solution, the 0.2 to 20% by weight, preferably 10% by weight, of the polymeric material contains in total, i.e. the total combined weight of the acrylamide polymer and the cellulose ether. After the solution has been applied, the fibers are dried, leaving a tough, non-sticky film (Size), which adheres firmly to the fibers, forms.

909850/0169

- ⁵ - H94865

Aqueous solutions of the film-forming sizes are applied to the glass fibers or composite molds the same "process known from view", e.g. by immersion, Spray on, brush on or roll on, so that the fibers have a uniform coating of the obtained solution applied. If there is an excess of the solution, it is allowed to run off the fibers, whereupon the wet fibers are dried.

Drying can be accomplished in any conventional manner. For example, the wetted fibers can be satisfactorily dried by storing them at normal room temperatures. Preferably, however, the drying process is accelerated by applying heat either with or without compressed air. The temperatures used for this purpose, up to the decomposition temperature of the size range, but sufficiently rapid drying speeds are generally from 30 bie 10 ⁰ C achieved.

If desired, the size according to the invention simply removed from the fibers again by placing them in the presence of oxygen at an elevated temperature heated or baked; this results in an oxidation of the organic components of the visual light marshes, iiormalervieise this will simply be at temperatures above 400 * C, however, below temperatures at which the

90985 ^ / 0169

/ ■
ο

the glass melts, reached "

The term "acrylanide polymers" relates to soluble polymers with a molecular weight of at least 10000 which are built up from polyalkane chains with a plurality of carboxamide substituents. These polymers are produced by homopolymerization of acrylamide or methacrylamide or by copolymerization of these monomers with other suitable monoethylenically unsaturated compounds copolymerizable therewith. If the comonomer used contains a water-solubilizing group, v / ie ζ.B ₀ in the (copolymers of acrylamide or methacrylamide with acrylic acid, methacrylic acid, maleic acid, vinylbenzylammonium compounds, for example trimethylvinylbenzylammonium chloride, vinylbenzenesulfonic acid, F-vinyloxazolidinone, F-vinyloxazolidinone, li-vinylorpholine, pyrrolorpholine, pyrrolorpholine and vinyl alcohol, the copolymer can have a significant

Contain portion of this comonomer. A preferred one Acrylamide polymer consists of a copolymer from 70 to 99 weight ^ acrylamide and 30 to 1 weight ^ acrylic acid. These polymers are usually obtained by polymerizing acrylamide under conditions such that 1 to 30 $ of the carboxamide groups present to carboxyl groups be hydrolyzed. Other suitable comonomers which do not contain such water-solubilizing groups',

BATH ORIGINAL

909850/0169

-5- U94865

include ζ, Β ethylene, butylene, styrene, methyl or ethyl esters of acrylic acid and methacrylic acid, vinyl chloride, vinylidene chloride, acrylonitrile, vinyl acetate, vinyl propionate, methyl vinyl ether and propyl vinyl ether o With these hydrophobic monomers, the amount used must not be so large that the water solubility of the obtained copolymers is deteriorated. In any case, the acrylamide homopolymers and copolymers required are practically water-soluble polymers with little or no cross-linking between the polymer chains, which in polymerized form contain at least 50 diol fibers of the monomers substituted with carboxamide groups.

I) The above-described acrylamide polymers are known and can be produced by any known procedure, which basically consists in : <\ i the monomers in a suitable solvent medium, for example water, in the presence of a chemical catalyst of the free radical type, are dispersed _o the polymerization is carried ^ then under controlled Temperaturbedingun s within the range of 40 to 140 ^ "Depending on the nature of the temperature conditions used and the nature of the reactants, it may be necessary in some cases, the polymerization reaction in a pressurized system to execute. Although the polymer sols produced in this way are used directly

909 8 5 0/0169 bathroom original

can, the polymer is usually obtained from the polymerization system as a test product. Vacuum drying or any other suitable separation method or combination of such methods can be used effectively for this purpose.

The applied here nonionic cellulose ethers may consist of one or more water soluble cellulose derivatives f, including hydroxyethyl cellulose, i'iethylcellulose, ethylcellulose, HydroxyäthylmethylcelluLose, hydroxypropyl methyl cellulose and similar cellulose ethers include. The processes for producing the cellulose ethers are known.

Specific examples of cellulose ethers which can be effectively used include methyl cellulose having a methoxyl degree of substitution of 1.6 to 2.7, i-ethylhydroxypropyl cellulose having a degree of methoxyl substitution of 1.4 to 1.9, or hydroxypropoxyl degree of substitution of 0.1 to 0.4. Specific hydroxyethyl cellulose ethers which can be effectively used include those having a hydroxyethoxyl degree of substitution from 0.7 to about 1.2.

Whether an acrylamide polymer or a cellulose ether is suitable Way water-soluble can be easily determined by adding a small amount of the polymer or the ether is dispersed in water. If it can be solved like this,

BATH ORIGINAL

909850/0169

that a homogeneous solution for the eye results, with large volume of additional water can be diluted, the polymer or the ether is for practice according to the Invention satisfactory »

In the preferred embodiment of the invention Acrylamide polymer and water-soluble cellulose ether each dissolved in separate amounts of water, so that homo-, gene solutions of the same result. These solutions are then mixed and, if necessary, additional water is added. given, so that the proportion of polymer solids in total in the range between 0.5 and about 20 wt ^ der Solution comes. This solution can be convenient for immersing either the individual optical fibers or the composite ones Molds made from such fibers can be used. However, the solution is preferably sprayed onto the fibers. Wake up Dipping the fibers or after spraying the fibers removes excess liquid sizing solution from the fibers expired. The wet fibers are then left to air dry at room temperature. Dependent on the time required for satisfactory drying depends on the humidity and temperature conditions between 1, minute or less up to 30 minutes or more. After the drying is complete, the fibers have an extreme smooth, uniform film of the sizing compound,

90 9 8 5 0/0169 bathroom original

which adheres firmly to its surface »

In other working methods, the solution of the ijchlichtemasse to be applied is brushed or rolled onto the fibers, so that there is a uniform coating of the solution on the surfaces of the fibers. If this up- method is used, it is usually not necessary to use a sequence step. The coated fibers can be exposed directly to a drying environment.

The following examples illustrate the invention. Examples 1-3

In 3 experiments, application solutions were prepared which each contained different relative amounts of the acrylamide polymer and a hydroxypropylmethyl cellulose ether, after which films made of this mass were cast onto glass plates. Each solution was at a y "- materials poured an aqueous solution containing 2 weight io to Polymerfest- \ IEVB of 6.3 in shape. After the films had dried, an attempt was made to separate the films from the glass substrate with a metal sheet. The relative amounts of the polymers used and the adhesion results in these tests and summarized in the following table

EAD OR: G! NAL

909850/0169

a distance from the glass plate is in the

Table listed,

Tabel

Example ratio of cellulose ether

to acrylamide polymer

liability

1 2 3

2.5: 1

1: 1

0.2: 1

very good very good good

The cellulose ether had a degree of hydroxypropoxyl substitution of 0.15 and a degree of ethoxyl substitution of 1.7. - an aqueous solution of the ether of 2 weight- ^ had a viscosity of 50 centipoise at 20 ⁰ C *

2) ■.

The acrylamide polymer consisted of a polyacrylamide with a molecular weight of at least 1 million, with 25 ^ of the previous carboxamide groups to carboxyl groups were hydrolyzed "

If the acrylamide polymer and the cellulose ether are used individually or in proportions outside the specified ranges, only poor adhesion is obtained.

909850/0169

BAD GRiOWAL

The sizing of continuous glass fibers is achieved in that glass fibers are pressed out of a container with molten glass through a platinum nozzle and from there are guided over a moving, continuous cloth belt, which is partially immersed in a sizing bath. ^ equal parts of a polyacrylamide with a molecular weight of 500,000, wherein a 5 ⁰ of the carboxamide groups hydrolyzed to carboxyl groups are Siert ψ, and a Methyleelluloseäthers, the hat.üaehdem a methoxyl degree of substitution of 1.9 and a viscosity of 50 centipoise, the fibers wetted on the Tape, whereby the fibers were uniformly coated with the sizing solution, the fibers were air-dried and wound onto a spool for later use »

If desired, other additives can be added to the light bath are incorporated, for example hydrocarbon oils as lubricants, emulsifiers and, if desired, cationic see means to still adhere the sizing to the glass increase,

BATH ORIGINAL

.904-8 5 07 Ό169

Claims (1)

PATENT CLAIMS 1. Sizing compound for silicic acid-containing fibers, thereby characterized in that it consists of an aqueous solution or contains an aqueous solution containing 0.2 to 20% by weight of a mixture of one part by weight of a water-soluble acrylic amide polymer and 0.1 to 10 parts by weight of a nonionic water-soluble one Contains cellulose ether. 2. Composition according to claim 1, characterized in that the aqueous solution contains 0.2 to 10 weight ^ of the mixture. 3. Ilasse according to claim 1 or 2, characterized in that that the acrylic amide polymer consists of a copolymer of 70 to 99 molar acrylamide and 30 to 1 molar acrylic acid consists and that the cellulose ether consists of a water-soluble liethylcelluloseather. 4. Composition according to claim 1 to 3 »characterized in that the cellulose ether consists of a mixed, water-soluble Ethyl hydroxypropyl cellulose ether. BATH ORIGINAL 90985D / 0169 ν. r.as. 'depending on iuit-i ruch 1 to ^, marked aaa by, ;?.:;. · ■ the Gej. lulose ether from a v / ater solution / ilyciroxyäthyjLeyliuloseäther ordered b. Vjiedte glass fiber, characterized by an adherent organic sizing in one .weight part üiiiefc · Goj oiyi.i '.- ren from 70 to' jy ί ^ Ι-ρ acrylamide and ;; U to 1 iioi- / u ji.fir.7LcrMure , as well as 0.1 to 1 gev / ichtst-ilei'i of a iiiohtionic water-soluble cellulose- o-eBchlichtete ijl ^ si'as also .ai «| _ruch 6, thereby ge - .; eiiiizeiciinet, -.iai.> the cellulose ether from a: water-soluble Liethyloelulose ether exists. Bo Sized glass fibers according to ^ nsj-ruch 6, characterized in that i; i: .- i the gelulose ester from a water-soluble mixed kethylhydroxyi ^ ropylcelluloseather consists, 9. Sized glass fibers according to claim 6, characterized in that then the cellulose ether from a water soluble E. hydroxyethyl cellulose ether is made up » BATH ORIGINAL 909850/0169