MXPA97002394A - Epdm compositions and processes to produce lasmis - Google Patents

Abstract

The present invention relates to a foamable EPDM composition comprising: EPDM, a carbon black having a CTAB of 50 to 60 m2 / g and a DBP of 90 to 115 cc / 100 g, and a blowing agent, wherein the black of coal is present in an amount of 50 to 250 p

Description

limitation, its surface areas, surface chemistry, aggregate sizes and particle sizes. The properties of carbon blacks are analytically determined by tests known in the art, including the test (C ), surface area of cetyltrimethalmmonium bromide and the (DBP) adsorption of dibutyl phthalate. In particular, carbon blacks have been used extensively as fillers and reinforcing pigments in the formation of EPDM compositions and in their preparation, which are intended to be used in weather-proof strip-type sponge applications. Weather seal strips in the form of sponges refer to EPDM compositions which, after being extruded or shaped and cured, give a profile containing cells or air voids and resembling a sponge. UHF microwave curing is one of the curing methods used in the manufacturing process of sponge strips against the weather. UHF microwave curing is increasingly important due to its high heating efficiency and its compatibility with environmental regulatory requirements and in the workplace. As understood in the art, UHF microwave curing refers to a curing process using ultra high frequency microwave, which P1162 / 97MX are frequencies of approximately 300 to 300,000 megahertz (megacycles per second or MHz). Conventional low carbon blacks such as ASTM N550 carbon black, ASTM N650 carbon black, ASTM N762 carbon black and ASTM N990 carbon black are widely used for incorporation into foamable EPDM compositions, as these blacks of carbon allow easy expansion (foaming). However, EPDM compositions incorporating low booster carbon blacks are not as receptive to UHF microwave curing as are the foamable EPDM compositions of the present invention. As a result of being more receptive to UHF microwave curing, the foamable EPDM compositions of the present invention have a faster heating rate than EPDM compositions incorporating similar amounts of low-strength carbon blacks. In addition, the cured and foamed EPDM compositions of the present invention exhibit lower sponge density and reduced sponge compression than EPDM compositions incorporating similar amounts of low reinforcing carbon blacks. In addition, the cured and foamed EPDM compositions of the present invention exhibit a smoother surface (by visually distorting) than is characteristic of P1162 / 97MX EPDM compositions that incorporate similar amounts of c.e blacks of low reinforcing carbon.

SUMMARY OF THE INVENTION We have discovered foamable EPDM compositions comprising: EPDM; a carbon black having a C (cetyl trimethylammonium bromide surface area) of 50 to 60 m2 / g (square meters per gram) and a DBP (dibutyl phthalate absorption value) of 90 to 115 cc / lOOg ( cubic centimeters of dibutyl phthalate per 100 grams of carbon black); and a blowing agent. The foamable EPDM compositions of the present invention incorporate carbon black in an amount of 50 to 250 ppc (parts by weight of carbon black versus 100 parts by weight of EPDM). Preferably, the foamable EPDM compositions are incorporated into the carbon black in an amount of 100 to 200 ppc. The EPDM foamable compositions of the present invention are advantageously used in applications where a rapid rate of UHF microwave heating is desired. One of these applications is the strip of P1162 / 97MX automotive sponge type weatherseal. An additional advantage of the foamable compositions of the present invention is that they have improved performance properties compared to EPDM compositions incorporating conventional blends of low-reinforcing carbon blacks. We have also discovered that cured EPDM compositions comprise: EPDM; and a carbon black that has a CTAB of 50 to 60 m / g, and a DBP of 90 to 115 cc / lOOg. The cured and foamed EPDM compositions of the present invention incorporate carbon black in an amount of 50 to 250 ppc. Preferably the cured and foamed EPDM compositions incorporate carbon black in an amount of 100 to 200 pph. The foamed and cured EPDM compositions of the present invention have a low sponge density and low sponge compression maintenance compared to EPDM compositions incorporating similar amounts of conventional low reinforcing carbon blacks. A further advantage of the cured and cured EPDM compositions of the present invention is that the cured and cured EPDM compositions have properties of P1162 / 97MX improved performance compared to EPDM compositions that incorporate similar amounts of conventional blends of low reinforcing carbon blacks. We have further discovered a process for producing cured and cured EPDM compositions comprising: mixing EPDM, a carbon black having a CTAB of 50 to 60 m2 / g and a DBP of 90 to 115 cc / lOOg and a blowing agent, and foaming and curing the resulting mixture, wherein the carbon black is present in an amount of 50 to 250 ppc. Preferably the process further comprises the step of extruding or shaping the resulting mixture of the EPDM, the carbon black and the blowing agent prior to curing the composition. Also, the process of the present invention is preferred where UHF microwave curing is used to cure the resulting mixture of EPDM, carbon black and blowing agent. It is also preferred to use a carbon black amount of 100 to 200 ppc in the process to produce cured and foamed EPDM compositions of the present invention. We have further discovered the advantageous use of cured and foamed EPDM compositions of the present invention as weatherseal strips. According to the present invention, a process for weather seal strips comprises: P1162 / 97MX seal a surface with a cured and foamed EPDM composition comprising EPDM and a carbon black having a CTAB 50 at 60m2 / g and a DBP of 90 to 115 cc / lOOg, where carbon black is present in a quantity of 50 to 250 ppc. Preferably, in the process for sealing with weather strips of the present invention, carbon black is present in an amount of 100 to 200 pph. Other advantages of the present invention will be apparent from the following more detailed description of the invention.

DETAILED DESCRIPTION OF THE INVENTION As stated above, the present invention provides foamable EPDM compositions; the cured and cured EPDM compositions; the processes for producing the cured and cured EPDM compositions; and the use of foamed and cured EPDM compositions as weather seal strips. Each of these aspects of the invention is described in greater detail in the following paragraphs. EPDM Foamable Compositions The present invention provides foamable EPDM compositions comprising: EPDM; P1162 / 97MX a carbon black having a CTAB of 50 to 60 m2 / g and a DBP of 90 to 115 cc / lOOg; and a blowing agent. Where carbon black is present in an amount of 50 to 250 ppc. Preferably, carbon black is present in an amount of 100 to 200 ppc. The amount of blowing agent used in the foamable EPDM composition of the present invention is an amount sufficient to expand (froth) the resulting composition. In general, the blowing agent is used in an amount of 2 to 15 ppc (parts by weight of blowing agent with respect to 100 parts by weight of EPDM). EPDM is well known and is obtained commercially from a variety of sources. Blowing agents that are suitable for use in the EPDM compositions of the present invention include any blowing agent, compatible with the EPDM blend and the carbon black. Suitable blowing agents include, without limitation: liquid or gaseous nitrogen, a halogenated hydrocarbon having a boiling point below 25 ° C; chemical blowing agents such as azodicarbonamide (AZDC), toluenesulfonyl hydrazide (TSH), oxybis (benzensulfonylhydrazide) (OBSH), sodium bicarbonate or activated forms thereof; and blowers type CELOG? N®, such as CELOGEN® AZ 199, CELOGEN® OT and CELOGEN P1162 / 97MX ® 754. CELOGEN is a registered trademark of Uniroyal Rubber Cotr.pany. The foamable EPDM compositions in the present invention may also contain conventional additives such as oils, stabilizers, oxides, acids, curing agents etc., which are known to those of ordinary skill in the art, as useful for incorporation during and in the formation of the EPDM compositions. The curing agents are added to the composition by mixing them before curing and before shaping or extruding the mixture. Curing agents useful for incorporation into EPDM compositions are known in the art and include any curing agent that is compatible with the EPDM, carbon black and blowing agent used. The foamable EPDM compositions of the present invention may be produced in any manner known to those of ordinary skill in the field of the production of EPDM compositions incorporating carbon blacks. A method for producing the compositions of the present invention, using a Banbury BR mixer, is set forth below. A Banbury BR mixer is started and maintained at a temperature of 45 ° C and at a rotor speed of 77 RPM. The EPDM is added to the mixer and P1162 / 97MX mixes for approximately 30 seconds. The oil and preferably the zinc oxide and the stearic acid, or the compositions having similar properties, are added to the EPDM and mixed for about 2 more minutes. The carbon black is added to the mixture and the temperature of the mixing chamber is inferred and maintained at a temperature below about 135 ° C. The blowing agent is preferably added to the EPDM / carbon black mixture. Typically, the carbon black / EPDM mixture is mixed for about 4.5 minutes. Blowing agents and curing agents (if used) are added to the mixture. Although one of the methods for producing the foamable EPDM composition of the present invention has already been described, the foamable EPDM compositions of this invention can be produced by other methods for the production of rubber or polymer compositions, known to those of ordinary skill in the art. this field .

Foamed and Cured EPDM Compositions The present invention also provides cured and foamed EPDM compositions comprising: EPDM and 50-250 ppc of a carbon black having a CTAB d = 50 to 60 m2 / g and a DBP of 90 to 115 cc / lOOg , P1162 / 97MX where carbon black is present in an amount of 50-250 ppc. Preferably, carbon black is present in an amount of 100-200 ppc. The cured and foamed EPDM compositions of this invention provide sponge profiles having lower sponge densities and a smoother surface appearance (when visually inspected), and less sponge compression maintenance, and other improved properties compared to conventional EPDM compositions. that incorporate similar amounts of low-reinforcing carbon blacks. As noted before, EPDM is well known and is obtained commercially from a variety of sources. In order to produce a cured and foamed EPDM composition of the present invention, the EPDM and the carbon black are mixed using known techniques, in general, for those of ordinary skill in the art. Ur. Blowing agent is mixed with EPDM and carbon black to provide the "foamed" characteristic. Suitable blowing agents include any blowing agent compatible with EPDM and carbon black, such as those listed in relation to the foamable EPDM compositions of the present invention. The amount of blowing agent that is incorporated into the mixture P1162 / 97HX of EPDM and carbon black is a sufficient amount to expand (froth) the resulting composition. In general, the blowing agent is used in an amount of 2 to 15 Ppc. The cured and foamed EPDM compositions of the present invention may also comprise conventional additives such as oils, stabilizers, oxides, acids, curing agents, etc., known to those of ordinary skill in the art as useful for incorporation into the formation of EPDM compositions and during said training. The curing agents are added to the composition by mixing before curing and before shaping or extruding the mixture. The curing agents useful for incorporation into the cured and cured EPDM compositions of the present invention are known in the art and include any curing agent compatible with the EPDM, carbon black and blowing agent used. The cured and foamed EPDM compositions of the present invention can be produced using conventional techniques, for example the techniques described above in relation to the EPDM compositions of the present invention. After mixing the EPDM, the carbon black, the blowing agent and the additives (if any) the compositions can be extruded or formed before the P1162 / 97MX cured, using conventionally available media. Curing can be done using any equipment commercially available for UHF microwave. A method that includes an extrusion step for curing an EPDM composition, to produce a foamed and cured EPDM composition of the present invention, is as follows, using a commercial Cober UHF microwave curing line (microwave frequency at 2450 MHz). A foamable EPDM composition is preformed by means of an extruder, then the extruded profile is fed through a hot air tunnel or the profile film is preheated and pre-cured. The EPDM profile is foamed and cured in a UHF microwave curing chamber at a suitable microwave power and the EPDM profile is subsequently cured continuously in another hot air tunnel at the end of the line, to stabilize the profile. Although a method for producing the cured and cured EPDM composition of the present invention has already been described, the cured and cured EPDM compositions of the present invention can be produced by other methods to produce rubber or polymer compositions known to those skilled in the art. this champ.

P1162 / 97MX Process for the production of cured and foamed EPDM compositions The present invention further provides a process for producing cured and foamed EPDM compositions comprising: mixing EPDM, a carbon black having a CTAB of 50 to 60 m2 / g and a DBP from 90 to 115 cc / 100 g and a blowing agent, - and foaming and curing the resulting mixture, wherein the carbon black is present in an amount of 50 to 250 pph, preferably 100 to 200 pph. Preferably the process further comprises the step of extruding or shaping the resulting mixture of the EPDM, the carbon black and the blowing agent before foaming and curing. It is also preferred to cure the resulting mixture of the EPDM, the carbon black and the blowing agent or the extruded or shaped mixture using UHF microwave. The amount of the blowing agent used in the process is an amount sufficient to expand (froth) the resulting composition. In general, the blowing agent is used in an amount of 2 to 15 ppc. The process for producing cured and foamed EPDM compositions of the present invention may further comprise the step of mixing an additive with the P1162 / 97MX mixture of EPDM, carbon black and blowing agent. Suitable additives for use in the process of this invention include conventional additives such as oils, stabilizers, oxides, acids, curing agents, etc., which are known to those of ordinary skill in the art, as useful for incorporation into EPDM compositions and during the formation of these. The curing agents are added to the composition by mixing them before curing and before shaping or extruding the mixture. The curing agents useful for incorporation into the EPDM compositions are known in the art and include any curing agent that is compatible with the EPDM, the carbon black and the blowing agent used. The mixing of the EPDM, the carbon black, the blowing agent and the additives (if any) can be carried out in any manner known to those of ordinary skill in the art. A mixing method using a Banbury BR mixer is described above in relation to the EPDM compositions of the present invention. In a preferred process of the present invention the process further comprises the step of extruding or shaping the resulting mixture of EPDM, carbon black, blowing agent and additive or additives, if any. The step of the extrusion or forming process can be carried out using any conventional means, P1162 / 97MX for example the medium described above in relation to the cured and cured EPDM compositions of the present invention, or the medium described in the following Example 2. In another preferred process of the present invention, the resulting mixture of EPDM, black Coal, blowing agent and additive or additives, if any, is cured using UHF microwave curing. In a more preferred process of the present invention, the resulting mixture of EPDM, carbon black, blowing agent and additive or additives, if any, is extruded or formed and then cured using UHF microwave curing. The UHF microwave curing step of the process of the present invention can be carried out using any equipment commercially available for UHF microwave. In general, the mixture of black carbon EPDM, blowing agent and additive or additives, if any, is cured at once, frequently and for a period of time such that the cured and foamed EPDM composition will have the desired properties for the intended end use. In a preferred embodiment of the process of the present invention, the UHF microwave curing step occurs at a frequency and for a period of time such that the cured and foamed EPDM composition will have a lower sponge density, a smoother surface appearance , a P1162 / 97MX maintenance of lower sponge compression and other improved properties compared to EPDM compositions incorporating conventional low-carbon blacks in equivalent loads. Suitable UHF microwave frequencies include, without limitation, frequencies of 300 to 300,000 MHz with 2450 MHz as the typical frequency. A suitable method of curing, including an extrusion step, is the method described above in relation to the cured and foamed EPDM compositions of the present invention. As will be recognized by those skilled in the art from the following description, the process for producing cured and foamed EPDM compositions of the present invention can be used to produce the cured and foamed EPDM compositions of the present invention. It should further be recognized that although the process of the present invention has been described in relation to a particular means of mixing, extrusion or forming and curing, the process is not limited to the described means and includes any other conventional means of mixing, extrusion or forming. and curing the EPDM compositions.

P1162 / 97MX Use of foamed and cured EPDM compositions as strips d | weather seal Additionally, the present invention relates to the use of the cured and foamed EPDM compositions of the present invention as weather seal strips. The process for the weather seal comprises: sealing a surface with a cured and foamed EPDM composition comprising EPDM and a carbon black having a CTAB of 50 to 60 m2 / g and a DBP of 90 to 115 cc / 100 g, wherein the carbon black is present in an amount of 50 to 250 pph, preferably 100 to 200 pph. The sealing step of the method, for the sealing strip according to the weather of the present invention, can also be carried out in any manner known to those having ordinary skill in this field, even in conventional ways for sealing a surface with a strip against the weather. The EPDM curing and foaming compositions can be produced in any conventional manner for the production of cured and foamed EPDM compositions and, in particular, by the methods described above in relation to the cured and foamed EPDM compositions of the present invention, and the process of the present invention. The cured and foamed EPDM compositions can also P1162 / 97MX include additives, such as the additives referred to above in relation to the cured and foamed EPDM compositions of the present invention. The effectiveness and advantage of the various aspects and embodiments of the present invention will be further illustrated by the following examples, wherein the following test procedures were used.

Analysis of carbon blacks The following test procedures were used in the determination and evaluation of the analytical properties of the carbon blacks used in the following examples. The DBP (dibutyl phthalate adsorption value) of the carbon black was determined according to the procedure set forth in ASTM D2414. The No. of 12 (iodine adsorption number) of the carbon blacks was determined according to the ASTM D1510 method. The CTAB value (absorption value of cetyltrimethyl ammonium bromide) of: the carbon blacks was determined according to the test method ASTM D3765-85. The dye resistance (dye) of the carbon blacks was determined according to the ASTM D3265-85a test procedure. The CDBP value (adsorption value of dibutyl phthalate) of the carbon blacks traded was determined according to the procedure set forth in ASTM D3493-86. P1162 / 97MX Evaluation of EPDM compositions The following test procedures were used in evaluating the performance properties of the EPDM compositions of the following examples. The receptivity of the UHF microwaves was measured in a Dielectric (supplied by Total Elastomers of France). The microwave UHF receptivity is characterized by a coefficient, a, which is defined as a = (150 ° C - 80 ° C) / (t150-t80) [° C / s] where -150 and tdO are the times they are needed for the samples to reach 150 ° and 80 ° C, respectively. a is the heating rate between the temperatures of 80 ° and 150CC. The performance of the cured and cured EPDM compositions is evaluated using the following procedures. a) Sponge Density Sponge density was measured in terms of pounds / foot: cubic using the following method. 1) The sample is sponge weight and the weight is recorded in bouquets; 2) the sample was completely immersed in a graduated cylinder filled with water (the specimen was graduated in milliliters (mi)) and the increase in volume was recorded P1162 / 97MX (volume of water displaced by the spcnja sample); 3) Sponge density was calculated from the following ratio: Sponge density (pounds / cubic foot) (weight / volume (g / ml)) x 62.4 (conversion factor) b) Sponge Compression Maintenance Sponge Compression Maintenance measures the ability of rubber compositions to retain the elastic properties after subjecting a sample to a constant deflection, for a specific time and temperature. Sponge comprehension maintenance was measured using the following procedure with a compression device consisting of two parallel plates between which the sample is compressed. The deflection was obtained by lowering the upper plate to the height of the spacers. The sponge profile was inserted, in the longitudinal direction, between the metal plates of the fastener. Three separators were placed to achieve a 50% compression between the samples. The fastener bolts were tightened so that the plates rested firmly on the spacers. The compression device containing the samples was placed in an oven P1162 / 97MX and maintained at 158 ° F for 22 hours. After a heating period of 22 hours, the compression device was removed from the oven and the samples were immediately removed from the compression device. The samples were cooled for 30 minutes and then their weight was measured up to one thousandth of an inch closer. Compression maintenance was calculated as Sponge Compression Maintenance = (TQ-T ^) / (TQ-TS) X 100% where: TQ = original height of the sponge T] _ = final height of the sponge Ts = thickness of the separator used.

Example 1 This example illustrates the greater receptivity to the UHF microwaves of EPDM compositions incorporating carbon blacks typical of the carbon blacks specified in the compositions and processes of the present invention, compared to EPDM compositions incorporating conventional carbon blacks of low reinforcement. The eight EPDM compositions were prepared by incorporating four different carbon blacks in each of the two different charge levels in EPDM. The carbon blacks A and B were used to produce compositions P1162 / 97MX EPDM RAÍ - RA2 and RB1 - RB2, respectively. Two control carbon blacks, C and D were used to produce EPDM compositions RC1-RC2 and RD1-RD2, respectively. The analytical properties of carbon blacks A-D were as shown in Table 1 below.

TABLE 1 - Analytical Properties of Carbon Blacks The compositions EPDM RAÍ, RA2, RB1, RB2, RC1, RC2, RD1 and RD2 were prepared by incorporating, each, carbon black, at 150 ppc and 200 ppc, in the EPDM composition shown below in Table 2. In the composition of Table 2, blowing agent was not used for the purpose of allow the evaluation of UHF microwave receptivity of each of the EPDM compositions.

P1162 / 97MX EPDM: EXXON VISTALON®5600 manufactured and sold by EXXON Corporation, Wilmington, Delaware, - Sunpar 2280: A proprietary oil manufactured and sold by Sum Oil Company; TMTDS: tetramethylthiuram disulfide; Butyl Zimate: a brand-name zinc dibutyldithiocarbonate manufactured by R.T. Vanderbilt Co., - Methyl Zimate: a brand-name zinc dimethyldithiocarbamate manufactured and sold by R. T. Vanderbilt Co.; P1162 / 97MX Suan R: a commercial 4, 4'-dithiodimorpholino manufactured and sold by Mons ato Co, St. Louis, Missouri. All the EPDM compositions in Table 2 (RAI to RD2) were produced in the following way. A Banbury BR mixer was started and maintained at a temperature of 45 ° C and at a rotor speed of 77 RPM. The EPDM was added to the mixer and mixed for approximately 30 seconds. Sumpar 2280 oil, zinc oxide and stearic acid were added to the EPDM and mixed for approximately 2 more minutes. The carbon black was added to the mixture and the temperature of the mixing chamber was cooled and maintained at a lower temperature of appropriately 135 ° C. The resulting mixture was mixed for approximately 4.5 minutes and then the TMTDS, the sulfur and the Butyl Zimate and the Methyl Zimate and sutam R were added to the mixture. The resulting mixture was mixed for approximately 1.5 minutes while the temperature was kept below about 135 ° C. UHF microwave receptivity, characterized by "a" of each EPDM composition of Table 2, was measured using the analytical techniques described herein. The results are shown in Table 3 below: P1162 / 97MX TABLE 3: The coefficient a (° C / seconds) of the EPDM Compositions < ue Contains Carbon Blacks at Two Different Charges As shown in Table 3, the EPDM compositions RAI, RA2, RB1 and RB2 incorporating carbon blacks typical of the carbon blacks incorporated in the EPDM compositions of the present invention had values greater than 150 and 200 parts by weight. , that the EPDM compositions RC1, RC2, RD1 and RD2 that incorporate similar amounts of conventional carbon blacks. From these results, it is evident that any composition incorporating EPDM and carbon blacks typical of carbon blacks incorporated in the EPDM compositions of the present invention, will heat up more quickly than EPDM compositions incorporating similar amounts of carbon blacks conventional Example 2 Three foamed EPDM compositions were prepared and P1162 / 97MX cured using carbon blacks A, B, C, and D to be set forth in Table 1. The foamed and cured EPDM compositions RE were prepared incorporating 130 ppc of carbon black A. The foamed and cured EPDM RF compositions were prepared by incorporating 130 ppc of carbon black B. The RG foamed and cured EPDM compositions were prepared by incorporating a mixture of 20 ppc of carbon black C and 110 ppc of carbon black D. The foamed and cured compositions EPDM RE, RF and RG they were prepared by incorporating carbon blacks AD into the foamable EPDM composition set forth in Table 4 below, and foaming and curing the compositions as described in the following paragraphs to Table 4.

P1162 / 97MX ROYALENE® 525: EPDM manufactured and sold by Uniroyal Chemical Company; Sunoar 2280 oil: A brand-name manufactured oil P1162 / 97MX and sold by Sun Oil Company; TE-28 G9: Processing aid MBT: 2-mercatobenzothiazole, used as accelerator Brown Factice: Vulcanized vegetable oil used as a plasticizer extender Ethyl Tellurac: Tellurium dietildithiocarbamate used as accelerator Butazarto nuggets: zinc dibutyl dithiocarbamate used as Sulfat accelerator: Dipenta methylene thiuram tetrasulfide used as an accelerator and sulfur donor. CELOGEN®A 199: azodicarbonamide, manufactured by Uniroyal Chemical Company, used as a blowing agent. The foamable EPDM compositions of Table 4 were heated and cured using a Cober-type commercial UHF microwave curing line with a microwave frequency set at 2450 MHz. The foamable EPDM compositions were made through an extruder and then passed through. of a hot air tunnel.

The foamable EPDM compositions were foamed and cured by heating in a UHF microwave curing chamber at 2450 MHz. The microwave power supply was adjusted to 4.8 KW (ilowats). The entry temperature of the foamable EPDM compositions to the P1162 / 97MX UHF microwave curing chamber inlet was 240 ° F. After foaming and curing, the EPDM profile was postcured by passing it through a second hot air tunnel at the end of the line. In order to evaluate the temperature rise produced by UHF microwave heating, for each of the cured and cured EPDM compositions (sponge profile), the temperature of these cured and foamed EPDM compositions was measured at the outlet of the Cured by UHF microwave. As noted above, the inlet temperature was also measured as foamable EPDM compositions entered the UHF microwave curing chamber. The results are established in Table 5.

TABLE 5 ELEVATION OF TEMPERATURE DURING HEATING BY UHF MICROWAVE (a Tempera, constant entry temperature (T¿) and an energy input of 4.8 KW) P1162 / 97MX As shown in Table 5, the cured and cured EPDM compositions, RE and RF of the present invention, showed a higher temperature rise (at a constant microwave power supply of 4.8 KW and at an inlet temperature constant T] _, 240 ° F) than the cured and cured EPDM compositions, RG which incorporate a similar amount of a conventional mixture of carbon blacks. The results of a higher temperature rise indicate that the cured and cured EPDM compositions of the present invention RE and RF, have a higher microwave UHF receptivity than the EPDM, RG compositions, which incorporate a similar amount of a conventional mixture of blacks of heat. These results further confirm the results obtained in example 1. The performance, in terms of the sponge density and the maintenance of sponge compression, of each of the foamed and cured EPDM compositions, RE, RF and RG, was evaluated. also using the techniques described here. The results are set forth in Table 6.

P1162 / 97MX TABLE 6 Sponge characteristics of cured and foamed EPDM compositions As shown in Table 6, the sponge density of the cured and cured EPDM compositions of the present invention, RE and RF is less than the sponge density of the cured and cured EPDM compositions, RG, which incorporate a similar amount of conventional blends of carbon blacks. The lower sponge density of the cured and foamed EPDM compositions of the present invention, RE and RF is preferred in a weather seal strip application. As shown in Table 6, the cured and foamed EPDM compositions of the present invention, RE and RF, had lower sponge compression maintenance than the cured and foamed EPDM compositions, RG, which incorporate a similar amount and a conventional mixture. of carbon blacks. The lower compression hold of the cured and foamed EPDM compositions of the present invention, RE and RF, is also preferred in a P1162 / 97MX application of seal strip against the weather. In addition, the EPDM foamed and cured compositions of the present invention, RE and RF, are characterized by having smoother surfaces than the RG foamed and cured EPDM compositions, as determined by visual inspection. It should be clearly understood that the forms of the present invention described herein are illustrative only and do not have a limiting sense as to the scope of the invention.

P1162 / 97MX

Claims (9)

1. NOVELTY OF THE INVENTION Having described the present invention, it is considered as a novelty and, therefore, the content of the following CLAIMS is claimed as property: 1. A foamable EPDM composition comprising: EPDM; a carbon black that has a CTAB of 50 to 60 m2 / g and a DBP of 90 to 115 cc / 100g; and a blowing agent, wherein the carbon black is present in an amount of 50 to 250 ppc.
2. 2. The EPDM composition of claim 1, wherein the carbon black is present in an amount of 100 to 200 ppc.
3. 3. A foamed and cured EPDM composition comprising: EPDM; and a carbon black having a CTAB of 50 to 60 m / g and a DBP of 90 to 115 cc / 100 g, where carbon black is present in an amount of 50 to 250 pph. .
4. The foamed and cured EPDM composition of claim 3, wherein the carbon black is present in a quantity of 100 to 200 pph.
5. 5. A process to produce EPDM compositions P1162 / 97MX foamed and cured comprising: mixing EPDM, a carbon black having a CTAB of 50 to 60 m2 / g and a DBP of 90 to 115 cc / lOOg, and a blowing agent, and foaming and curing the resulting mixture , where carbon black is present in an amount of 50 to 250 ppc.
6. 6. The foamed and cured EPDM composition of claim 5, further comprising the step of extruding or shaping the resultant mixture of the EPDM, the carbon black and the blowing agent prior to foaming and curing.
7. The process according to claim 5, wherein the mixture is cured using UHF microwave.
8. The process according to claim 6, wherein the mixture is cured using UHF microwave.
9. 9. The process according to claim 8, wherein the carbon black is present in an amount of 100 to 200 pph. THE. A process for sealing a surface with an anti-weather strip comprising: sealing the surface with a cured and foamed EPDM composition comprising EPDM and a carbon black having a CTAB of 50 to 60 m2 / g, and a DBP from 90 to 115 cc / lOOg, where carbon black is present in an amount of 50 to 250 pph. P1162 / 97MX Ll. The process for sealing with a weather strip of claim 10, wherein the carbon black is present in an amount of 100 to 200 ppc. P1162 / 97MX