GB1561414A

GB1561414A - 5 - norbornene - 2 - methyl-phosphitas and phophate and their use as polymer antiozonants

Info

Publication number: GB1561414A
Application number: GB25689/77A
Authority: GB
Original assignee: EI Du Pont de Nemours and Co
Current assignee: EIDP Inc
Priority date: 1976-06-21
Filing date: 1977-06-20
Publication date: 1980-02-20
Also published as: FR2364221A1; DE2727584C2; DE2727584A1; FR2364221B1

Description

(54) 5-NORBORENE-2-METHYL PHOSPHITES AND PHOSPHATE AND THEIR USE AS POLYMER ANTIQZONANTS (71) We, E. I. DU PONT DE NEMOURS AND COMPANY, a corporation organised and existing under the laws of the State of Delaware, located at Wilmington.

State of Delaware, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to certain phosphite and phosphate esters of 5-norbornene-2-methanol and to their use as antiozonants and/or flex resistance aids in various polymers and polymer blends.

Elastomeric chloroprene polymer vulcanizates are quite resistant to ozone at normal temperature but are more readily degraded at elevated temperatures, especially when flexed or stretched. Other polymer vulcanizates are less resistant to ozone than chloroprene polymer vulcanizates. Various anti-ozonants are commercially available and usually are incorporated in such polymer formulations.

While many such additives provide a good degree of protection against ozone deterioration, certain commercial antiozonants cause prematare curing of polymer stocks, while most cause discoloration or staining of the polymer vulcanizates. There presently appears to be only one nonstaining antiozonant commercially available.

We have now found a new class of phosphites and phosphates of 5-norbornene-2methanol which are very good antiozonants in chloroprene polymers. Mixtures of such esters are also effective antiozonants.

Thus according to one aspect of the present invention there is provided a composition comprising bis(5 - norbornene - 2 - methyl)phosphite, tris(3 - norbornene - 2 - methyl)phosphite, tris(5- norbornene - 2 - methyl)phosphate and 5 - norbornene - 2 - methanol.

As stated above the individual component ester compounds of the above composition according to the invention also possess an antiozonant property so that according to further aspects of the persent invention there are provided bis(5 - norbornene - 2 - methyl)phosphite; tris(5 - norbornene - 2 - methyl)phosphite; and tris(5 - norbornene - 2 - methyl)phosphate.

The above new esters and the composition containing them according to the invention are useful in the formulation of vulcanizable polymer compositions.

Thus according to a still further aspect of the present invention there are provided vulcanisable compositions comprising at least one polymer selected from A. chloroprene homopolymers; B. chloroprene/sulfur copolymers; C. chlorinated isobutylene/isoprene co polymers; and D. a blend of any of the above polymers A to C with one or more styrene/ butadiene copolymers or with natural rubber, the proportion of the poly mer A, B or C being at least 50 weight percent of the blend; wherein 0.5 to 5 parts by weight, per 100 parts by weight of the polymer or polymer blend, of at least one of the above compounds or composition according to the invention are incorporated into the polymer or polymer blend.

Vulcanised polymers having an improved ozone resistance can be prepared by vulcanized tion of the vulcanizable composition according to the invention.

According to another aspect of the present invention there is provided a process for the preparation of a vulcanizable composition which comprises incorporating at least one compound or composition according to the invention into a polymer selected from A. chloroprene homopolymers; B. chloroprene/sulfur copolymers; C. chlorinated isobutylene/isoprene copoly mers; and D. a blend of any of the above polymers A to C with one or more styrene/ butadiene copolymers or with natural rubber, the proportion of the polymer A, B or C being at least 50 weight percent of the blend; the proportion of compound or composition incor porated being from 0.5 to 5 parts by weight per 100 parts of the poly mer or polymer blend.

It has also been discovered that the same esters, used in the same amounts, improve the flex resistance of chloroprene copolymers with sulfur (B) and of their blends with either styrene/butadiene copolymers or natural rubber (D).

The S-norbomene-2-methyl radical can be represented by the following formula:

wherein CH groups are present in all positions except 3 and 7, and CH2 groups are present in positions 3 and 7.

The phosphate and phosphites of the present invention are rather difficult to isolate in their pure state regardless of the method by which they are made, a mixture of all three compounds, normally also containing some 5-nor- bornene-2-methanol, usually being obtained.

For the purpose of the present invention, a mixture of all three esters is satisfactory, and isolation and purification of each individual ester is not required. Any free 5-norbornene2-methanol present in the mixture is harmless. The relative proportion of each component of the mixture can be readily ascertained by known analytical techniques, especially by combining gas chromatography with mass spectrometry.

Depending on the particular technique used, the proportions of the various components of the product mixture will vary. Since, however, each of the esters in the mixture has antiozonant properties, it is not necessary for practical purposes to isolate any particular ester from the mixture. Usually, mixtures of bis(5 - norbornene - 2 methyl) phosphite, tris(5 - norbornene - 2 - methyl) phosphite, tris(5 - norbornene - 2 - methyl) phospate, and S - norbornene - 2 - methanol containing about 30-70 weight percent of tris(5 - norbornene - 2 - methyl) phosphite are obtained by reaction of PCIs with S - norbomene - 2- methanol in the presence of a base. Those mixtures, especially those wherein the proportion of tris(5-norbornene-2-methyl) phosphite is at least 40 weight percent, are valuable antiozonants. Other synthetic methods yield different proportions of products. As the level of tris(5-norbornene-2-methyl) phosphite in the mixture increase, the total amount of the mixture required to produce satisfactory ozone resistance decreases. For the best ozone protection without undesirable changes in other properties of the polymers, at the most reasonable cost, it is preferred to use about 1-3 parts by weight of the ester or ester mixture per 100 parts by weight of polymer or polymer blend.

The homopolymers, copolymers, and polymer blends in which the antiozonants of this invention are used are well known in the art and either are commercially available or can be made or blended according to available patent literature or technical literature.

Normally, the phosphate and phosphites of the present invention will be added to standard vulcanization recipes of polymers Standard vulcanization recipes for the chloroprene polymer and the blends are described in Murray and Thompson, The Neoprenes, E. I. du Pont de Nemours and Co., 1963, chapters III and V. The recipes normally include metal oxides, reinforcing agents and fillers, antioxidants, vulcanization agents such as sulfur, retarders and accelerators and plasticizers. In recipes containing elemental sulfur, the level of sulfur preferably should not exceed about 4 parts by weight per 100 parts by weight of polymer because otherwise the antiozonant activity of the active ingredients is reduced.

However, the amount of sulfur usually is below this level. Incorporation of the antiozonants into the polymer can be conveniently accomplished by blending with the polymer and any other ingredients of the recipe on a rubber mill, in a Banbury mixer, or in any other suitable mixing equipment.

It is also possible to add these esters to chloroprene polymer latex prior to the isolation of polymer therefrom. The polymer ;s isolated by standard techniques, such as freeze roll isolation followed by hot air drying.

The antiozonant effect of the compounds of this invention can be determined either in a static or in a dynamic test. Both tests expose cured elastomer samples to ozone in a test chamber at 40 C. For static exposures, samples of the vulcanizates, prepared as described in the following examples, 0.64 X 0.19 X 15.24 cm in dimension, mounted on varnished wooden racks, were subjected to the indicated tensile strains. The dynamic tests were carried out by the "roller" method described in Rubber Chemistry and Technology 32, 1119 (1959). The test pieces were flexed at a rate of 30 cycles per minute. The number of hours required to produce a given degree of cracking was observed.

The DeMattia flex resistance was measured by ASTM Method 813-59 (1970).

The gas chromatographic analyses in the following examples were made using a Hewlett Packard 5750 chromatograph, detector, and a lmv recorder. The 304-stainless steel column contained a silicone oil (OV-1, available from Supelco, Bellefonte, Pennsylvania) partitioning liquid on a Chromsorb (registered Trade Mark) W-HP [Celite (registered Trade Mark) Div., Joluí-Manville Product Corp.] support.

The injection port was at 250 C, the detector at 3300 C, the carrier gas argon, and the column temperature was programmed from 900 C at 10 C/min. to 2500 C and hold.

The gas chromatograph was directly coupled to a mass spectrometer in such a manner that any chemical compound whose peak appeared on the gas chromatogram could be swept directly into the ionization chamber of the mass spectrometer, where its molecular ion weight was determined. Either a Hewlett-Packard G.C.-mass spectrometer Model 5981A or Du Pont G.C.-mass spectremeter Model 491 with chemical ionization source was used.

In the illustrative examples below, all parts proportions, and percentages are by weight unless otherwise indicated.

TEST POLYMERS Polymer A a a sulfur/chloroprene copolymer prepared by the procedure of Example 1 of U.S.

3,920,623, to A. A. Khan. The Mooney viscosity of the polymer is 55-65 (ASTM D-1646).

Pdymer B - a sulfur/chloroprene copolymer sold as Neoprene GRT by E. I. du Pont de Nemours and Company, Inc., of Mooney viscosity 52.

This copolymer does not contain antiozonants.

Polymer C - a polychloroprene sold as Neoprene W by E. I. du Pont de Nemours and Company, Inc., of Mooney Viscosity 50. This polymer does not contain antiozonants.

Polymer D - a sulfur/chloroprene copolymer prepared by the procedure of Polymer A. Polymerization is stopped by adding an emulsion that contains 1.2 parts of Additive II (see below) based on unstripped emulsion solids in addition to the conventional ingredients. The unpolymerized monomer is removed, and the latex is aged at pH 12.2 for 8 hours. The pH is adjusted to 3.6 with acetic acid, and the polymer is isolated on a freeze roll and subsequently hot air dried.

ACTIVE INGREDIENTS Example I.

Tris (5-Norbornene-2-methyl Phosphite Sodium metal (0.5 g) was dissolved at an elevated temperature in 1000 g of freshly distilled 5-norbornene-2-methanol under a nitrogen atmosphere. The solution was cooled to room temperature, and 686 g triphenylphosphite was added. The mixture was heated to 1000 C for 36 hours. Excess S-norbornene-2methanol and byproduct phenol were removed by vacuum distillation. The viscous off-white liquid residue (863.3 g) was added to 50 parts decolorizing carbon ["Norit" (registered Trade Mark) A, product of American Norit Co.] and stirred at room temperature for one hour. After removal of the carbon black by filtration under nitrogen, 811.2 g of a liquid were recovered. A 128.8 g portion of the liquid was distilled and the following three fractions collected: Fraction 1: 18.6 g, b.p. 185199 C/0.3 0.68 mmHg.

Fraction II: 42.5 g, b.p. 194-1960 C/0.45- 0.60 mmHg.

Fraction III: 59.5 g, b.p. 195197 C/0.45-- 0.60 mmHg.

Gas chromatographic analyses determined that the fractions contained, respectively, 79, 81, and 83 area % tris(5-norbornene-2- methyl) phosphite.

Example II.

Polymer Additive I Phosphorus trichloride (68.5 g) was dissolved in 100 ml petroleum ether and cooled with dry ice. A solution of S-norborene-2- methanol (186 g.) and pyridine (119 g.) dis solved in 200 ml. petroleum ether was added dropwise with stirring to the PCls solution, The addition was made at such a rate that the temperature of the exothermic reaction did not rise above 00 C. After completion of the addition, the mixture was stirred at room temperature for an hour. Pyridine hydrochloride was removed by filtration and the filtrate dried over potassium carbonate. Solvent was stripped under reduced pressure. The residue, a yellowish liquid, had the following gas chromatographic analysis (area %): S-norbornene-2-methanol 42% bis (3-norbornene-2-methyl) )phosphite 17% tris(5-norbornene-2-methyl) phosphite 22 ,C tris(5-norbornene-2-methyl) phosphate 15 Example III.

Polymer Additive II A mixture of 0.3 g. sodium and 314 g. 5norbornene-2-methanol was allowed to react at 800 C. for about 3 hours under a nitrogen atmosphere. The solution was cooled to room temperature, and 261.5 g. triphenyl phosphite was added. The reaction mixture was stirred at room temperature for about 15 hours under a nitrogen atmosphere. Removal of volatiles gave 331.0 g. of residue having the following composition, as determined by gas chromatography: 5-norbornene-2-methanol 13.9 area bis(5-norbornene-2-methyl) phosphite 29.5 area % tris (S-norbornene-2-methyl) phosphite 41.1 area % tris(5-norbornene-2-methyl) phosphate 3.3 area % Small additional peaks due to unknown compounds also were observed.

Example IV.

Polymer Additive III A mixture of 0.5 g. sodium and 1000 g.

5-norbomene-2-methanol was allowed to react at 800 C. for about 3 hours under a nitro gen atmosphere. The solution was cooled to about 50 C., and 686 g. triphenyl phosphite was added. After the addition, the mixture was heated at 100" C. for about 1S hours. Volatiles, consisting primarily of excess 5-norbornene-2-methanol and phenol, were removed under vacuum, and the resulting crude pro duct, 864.3., was treated with 54 g. activated charcoal. The purified product, 815.6 g., was shown by gas chromatography to have the following composition: 5-norbornene-2-methanol 5.8 area % bis (S -norbornene-2-methyl) phosphite 15.9 area tris(5-norbornene-2-methyl) phosphite 65.5 area % tris(5-norbornene-2-methyl) phosphate 0.7 area % Small additional peaks were observed but not identified.

Example V.

Polymer Additive IV A mixture of 372 g. 5-norbornene-2-methanol and 303 g. triethylamine was slowly added with vigorous agitation to a solution of 206 g. phosphorus trichloride in 700 ml. benzene at O" C. The addition was made at such a rate that the temperature of the reaction mixture did not exceed 20 C. The addition took 4 hours. The temperature of the reaction mixture was then raised to 250 C. and a further 193 g. 5-norbornene-2-methanol was added.

After about I6 hours at room temperature, the reaction mixture was filtered, and the filtrate extracted with 250 ml. water and dried over sodium sulfate. After removal of volatiles, there was obtained 401.3 g. of product, which was vacuum distilled to give a fraction of b.p.

157160 C. (0.5 mm Hg). This fraction contained 8 area % S-norbomene-2-methanol and 91% bis(5-norbornene-2-methyl phosphite.

Example VI.

Polymer Additive V 5-Norbornene-2-methanol (186 g.), 130 g. pyridine, and 300 ml. benzene were added to a one-liter flask equipped with a reflux condenser protected by a calcium chloride drying tube, a mechanical stirrer, a dropping funnel, and a thermometer. The mixture was cooled to about 0 C. A solution of 76.5 g. phosphorus oxychloride in 50 ml. benezene was added dropwise with stirring over a period of 2 hours. The reaction mixture temperature was kept at 309 C. or less by external cooling.

After the addition, the reaction mixture was stirred for 30 minutes at about 300 C. and then heated at reflux for 2 hours. After cooling, precipitated pyridine hydrochloride was removed bv filtration, and the precipitate washes wfth 50 ml. benzene. rile combined filtrate and washing were extracted twice with 250-ml. portions of cold water and then dried over anhydrous sodium sulfate. Solvent was removed under vacuum and the resulting product analyzed by gas chromatography.

The product had the following composition: tris(5-norbornene-2-methyl) phosphate 95.2 area % S-norbornene-2-methanol OA2 area % tris (5 -norbornene-2-methyl ) phosphite 0.82 area % In the following examples, polymer masterbatches were prepared as shown. In most cases, control samples without an additive of this invention were also tested.

EXAMPLE 1 MASTERBATCH PREPARATION Masterbatch 1 Masterbatch 2 Polymer A 100 Polymer B 100 Stearic Acid 1.5 1.5 Antidegradanta) 2 2 Magnesia 4 4 General Purpose Furnace Black 45 45 Aromatic Oil b) 5 5 Zinc Oxide 5 5 162.5 162.5 a) Mixture of 65% N-phenyl--naphthylamine, 35% N,N '-diphenyl-para-phenylenediamine, sold as "Akroflex" CD, by E. I. du Pont de Nemours and Company. b) Sold as "Sundex" 790, by Sun Oil Company FORMULATION AND TESTING 1 2 3 4 Masterbatch 162.5 162.5 - Masterbatch 2 - - 162.5 162.5 Additive I - 2 - 0.8 Press Cure: 35 Min. at 1530C.

DeMattia Flex (2-1/4" stroke; 0.08" pierced) Original Cut growth at 1.1 x 106 flexes 0.2 in. 0 - 103 flexes to 0.5 in. growth > 1100 > 1100 15.7 48 Aged 3 Days at 2500F.

Cut growth at 1.26 x 106 flexes > 0.5 in. 0.02 in. 103 flexes to 0.5 in. growth 596 > 1260 < 1.5 3.5 EXAMPLE 2 MASTERBATCH PREPARATION Masterbatch 3 Polymer C 100 Stearic Acid 0.5 Magnesia 4 Semi-Reinforcing Carbon Black 58 Naphthenic Oil 10 Antioxidant b) 2 Zinc Oxide 5 2-Mercapto-2-imidazoline 0.75 Tetramethylthiuram Disulfide 0.5 180.75 a) Sold as "Circo" LP Oil, by Sun Oil Co. b) 2,2 '-Methylenebis(-tert-butyl-p-cresol), sold as Antioxidant 2246, by American Cyanamid Co.

FORMULATION AND TESTING 1 ~ 2 3 Masterbatch 3 180.75 180.75 180.75 Diaryl-p-phenylenediamine c) - 2 Additive I - 2 c) Sold as "Akroflex" AZ, by E.I. du Pont de Nemours and Company Press Cure: 20 Min. at 1530C.

Ozone Resistance (3 ppm at 400C.) Dynamic Original Hrs. to Bad Cracking 3 11 32 Aged 3 Days at 1210C.

Hrs. to Bad Cracking 32 62 196 Static (40% Elongation) Original Hrs. to Break 13 > 300 > 300 Aged 7 Days at 100 cm.

Hrs. to Break 42 74 > 300 EXAMPLE 3 FORMULATION AND TESTING 1 2 3 4 5 6 Masterbatch 162.5 162.5 162.5 - - Masterbatch 2 - - - 162.5 162.5 162.5 Antiozonant I a) - 1 - - 2 Additive I - - 1 - - 2 a) Mixture of 5-norbornene-2-methyl succinate (25%), glutarate (50%), and adipate (25%) Stress-Strain Properties (Press Cure 30 Minutes at 153 C.) Hardness, Shore A 66 64 60 70 66 64 100% Modulus, psi 405 345 370 600 440 430 Tensile Strngth, psi 3595 3445 3115 3400 3240 3115 Elongation, % 630 670 610 420 510 500 DeMattia Flex (2-" stroke; 0.08" pierced) Original 10 flexes to 0.5 in. growth - - - 29 220 472 Cut growth at 1.06 x 106 flexes 0.18 in. 0 0 - - Aged 3 Days at 121 C.

10 flexes to 0.5 in. growth 611 > 1310 > 1310 < 1.5 33.3 70 Cut growth at 1.31 x 106 flexes > 0.5 in. 0.22 in. 0.08 in. - - Ozone Resistance (3 ppm. at 40 C.) Dynamic Original Hrs. to Bad Cracking 39 39 47 31.5 61.5 91.5 Aged 7 Days at 100 C.

Hrs.to Bad Cracking 29.5 29.5 35 29.5 74.5 163.5 EXAMPLE 4 FORMULATION AND TESTING 1 2 Polymer D - 100 Polymer A 100 Stearic Acid 0.5 0.5 Magnesia 4 4 N-Phenyl-α-Naphthylamine 2 2 General Purpose Furnace Black 45 45 Intermediate Super-Abrasion Carbon Black 10 10 Aromatic Oil a 5 5 Zinc Oxide 5 5 Additive II 1.2 b) a) Sold as "Sundex" 790, by Sun Oil Co. b) See polymer description.

Mooney Scorch (121 C.) Minimum Value 42 41 Minutes to 2 Pt. Rise 26 > 30 Press Cure: 30 Min. at 1530C.

Ozone Resistance (3 ppm at 400C.) Aged 3.5 Months at 250C.

Dynamic Hrs. to Bad Cracking 19 32 Additional Aging 7 Days at 1000C.

H:s. to Bad Cracking 41 86 EXAMPLE 5 FORMULATION AND TESTING 1 2 Natural Rubber a) 50 50 Polymer C 50 50 Naphthenic Oil b) 10 10 Semi-Reinforcing Carbon Black 30 30 Stearic Acid 2 2 Zinc Oxide 4 4 N-Cyclohexyl-2-Benzothiazole Sulfenamide 0.6 0.6 Diphenylguanidine 0.3 0.3 Sulfur 1.3 1.3 Antioxidant c) 2 2 Additive I 2 a) Natural Rubber RSS&num;1 Breakdown b) Sold as "Circo" LP, by Sun Oil Co. c) 2,2'-Methylenebis(6-t-butyl-p-cresol), sold as "Antioxidant" 2246, by American Cyanamid Co.

Press Cure: 15 Min. at 1600C.

Ozone Resistance (0.5 ppm at 400C.) Dynamic Hrs. to Bad Cracking 17 62 Static 20% Elongation, Hrs. to Break 52 > 200 40% Elongation, Hrs. to Break 21 > 200 EXAMPLE 6 FORMULATION AND TESTING 1 2 3 Polymer C 50 50 50 Styrene-Butadiene Copolymer a) 50 50 50 Semi-Reinforcing Carbon Black 30 30 30 Naphthenic Oil 10 10 10 Stearic Acid 2 2 2 Antioxidant b) 2 2 2 N-Cyclohexyl-2-Benzothiazole Sulfenamide 006 0.6 0.6 Diphenylguanidine 0g3 0.3 0.3 Sulfur 1g3 1.3 1.3 Zinc Oxide 5 5 5 Additive II - 2 Additive III - - 2 a) SBR 1502, from Phillips Petroleum Co. b) Octylated Diphenylamine, sold as "Antox" N, by E. I. du Pont de Nemours and Company Press Cure: 25 Min. at 1770C.

OzoneResistance(3 ppm at400C.) Dynamic Original Hrs. to Bad Cracking 6 27 40 Aged 7 Days at 100 C.

Hrs. to Bad Cracking 10.5 23.5 375 Static (40% Elongation) Original Hrs. to Break 28 > 170 > 170 EXAMPLE 7 FORMULATION AND TESTING 1 2 3 Polymer C 100 100 100 Titanium Dioxide a) 30 30 30 Aluminum Silicate b) 30 30 30 Stearic Acid 2 2 2 Magnesia 4 4 4 Zinc Oxide 5 5 5 Antiozonant I c) - 2 - Additive II - - 2 Sulfur 1 I 1 Di-ortho- tolylguanidine 1 1 1 Tetramethylthiuram Monosulfide 1 1 1 a) "Ti-Pure" 902, from E. I. du Pont de Nemours Company b) "Optiwhite" Clay, from E. W. Kauffman Co. c) Mixture of 5-norbornene-2-methyl succinate (25%), glutarate (50%), and adipate (25%) Press Cure: 30 Min. at 1530C.

Ozone Resistance (3 ppm at 400C.) Dynamic Original Hrs. to Bad Cracking 14 22 45 Aged 7 Days at 1000C.

Hrs. to Bad Cracking 21.5 27.5 83.5 Static (40% Elongation) Original Hrs. to Break 18 27.5 > 128.5 EXAMPLE 8 FORMULATION AND TESTING 1 2 3 4 Chlorinated Isobutylene-Isoprene Copolymera) 50 50 50 50 Pale Crepe Natural Rubber 50 50 - Styrene-Butadiene Copolymer b) - - 50 50 Titanium Dioxide 35 35 35 35 Aluminum Silicate c) 40 40 40 40 Stearic Acid 1 1 1 1 Additive II 2 - 2 Zinc Oxide 5 5 5 5 Sulfur 0.7 0.7 0.7 0.7 2,21-Benzothiazyl Disulfide 0.75 0.75 0.75 0.75 Alkyl Phenol Disulfided) 1.25 1.25 1.25 1.25 a) Butyl HT-1068, from Egicon (registered Trade Mark) Chemicals Co. b) SBR 1502, from Phillips Petroeurn Co. c) Chemically modified aluminum silicate, sold as "Nucap" 290, by J. M. Huber Co. d) Sold as "Vultac" 5, by Pennwalt Co.

Press Cure: 30 Min. at 1530C.

Stress-Strain Properties Hardness, A 47 39 46 41 100% Modulus, psi 180 110 150 110 Tensile Strength, psi 2020 2020 1880 960 Elongation, % 540 640 930 910 Ozone Resistance (3 ppm at 400C.) Dynamic Hrs. to Bad Cracking 11 > 122.5 32.5 > 122.5 Static - 40% Elongation Hrs. to Break 67.5 > 72 20.5 > 72 EXAMPLE 9 MASTERBATCH PREPARATIOt Masterbatch 4 Polymer C Pale Crepe Natural Rubber 50 Semi-Reinforcing Carbon Black 30 Naphthenic Oila) 10 Stearic Acid 2 Antioxidant b) 2 Zinc Oxide 5 N-Cyclohexyl-2-Benzothiazyl Sulphenamidec) 0.6 Diphenylguanidine ~ 0.3 Sulfur 1.3 151.2 a) Sold as "Circo" LP Oil, by Sun Oil Co. b) Octylated Diphenylamine, sold as "ANTOX" N, by E. I. du Pont de Nemours and Company FORMULATION AND TESTING 1 2 3 4 Masterbatch 4 151.2 151.2 151.2 151.2 Additive none IV V III Parts - 2.4 2.28 2 Norbornene Content (Parts). - 1.55 1.47 1.21 Press Cure: 30 Min. at 1530C.

Stress-Strain Properties Shore A Hardness 42 36 37 37 300% Modulus, psi 640 500 440 495 Tensile Strength, psi 2190 1480 1760 1610 Elongation, % 580 540 640 555 Ozone Resistance Static (40% Elongation), 3 ppm at 400C.

Original (Hrs. to Break) 43.5 > 127 > 127 > 127 Aged 7 Days at 100CC. (Hrs. to Break) 37.5 > 232 > 232 > 232 Dynamic (0.5 ppm at 400C.) Original (Hrs. to Bad Cracking) 41 96 54 96 Aged 7 Days at 1000C. (Hrs to Bad Cracking) 13 39:5 95.5 > 95.5 EXAMPLE 10 Polymer C 70 Styrene-Butadiene Copolymer a) 30 Stearic Acid 1 Medium Thermal Black 85 Fast Extruding Furnace Black 15 Aromatic Oil b) 20 Polyethylene Processing Aid 2 Magnesia 2 Dinitro sopentamethylenetetramine 10 Zinc Oxide 5 Pentaerythritol 5 2Mercapto-2-lmidazoline 2 Di ethylthioure a 2 Sulfur 1 Octylated Diphenylamine c) 1.5 Antiozonant As Indicated a) SBR 1502, from Phillips Petroleum Co. b) Sold as "Sundex" 790, by Sun Oil Co. c) Sold as "Octamine", by Uniroyal Co.

The rubber compound was extruded through a 1" x 1/4" die using a 2?' diameter Royal extruder. The extruded rubber compound was placed in a hot air oven at 1910C. for 8 minutes. The resultant cured product was a closed cell sponge.

Ozone Resistance of Looped Test Specimens (ASTM D-518, Procedure B) (0.5 ppm Ozone) Rating 10 = no attack; Rating 0 = very severe attack (failure) 1 2 3 4 5 Additive II 0.3 0.6 - - Arylamine Antiozonant a) - 0.6 1.2 a) 50% N-phenyl-ss-napthyl amine; 50% diaryl-p-phenylene diamine. sold as "Akroflex" DAZ, by E. I. du Pont de Nemours and Company.

Hours Exposed Rating 24 10 10 10 10 10 48 10 10 10 10 8 96 10 10 8 10 5 475 10 10 6 10 0

Claims

WHAT WE CLAIM IS:

1. A composition comprising bis(5-norbor nene - 2 - methyl)phosphite, tris(5 - norbor. nene - 2 - methyl)phosphite, tris(5 - nor bornene - 2 - methyl)phosphate and 5norbornene - 2 - methanol.

2. Bis(5 - norborene - 2 - methyl)phosphite.

3. Tris(5 - norbornene - 2 - methyl)phos phite.

4. Tris(3 - norborene - 2 - methyl)phosphate.

5. Vulcanisable compositions comprising at least one polymer selected from A. chloroprene homopolymers; B. chloroprene/sulfur copolymers; C. chlorinated isobutylene/isoprene copolymers; and D. a blend of any of the above polymers A to C with one or more styrene/butadiene copolymers or with natural rubber, the proportion of the polymer A, B or C being at least 50 weight percent of the blend; wherein 0.5 to 5 parts by weight per 100 parts by weight of the polymer or polymer blend, of at least one of the compounds claimed in claims 2 to 4 or of the composition claimed in claim 1 are incorporated into the polymer or polymer blend.

6. A composition as claimed in claim 5 wherein the composition claimed in claim 1 is incorporated into the polymer or polymer blend.

7. Compositions as claimed in claim 6 wherein a composition as claimed in claim 1 in which tris(5-norbornene-2-methyl)phos phite predominates is incorporated into the polymer or polymer blend.

8. Compositions as claimed in any of claims 5 to 7 wherein the polymer comprises a chloroprene homopolymer or a chloroprene/ sulfur copolymer.

9. Compositions as claimed in claim 8 wherein the proportion of sulphur in the chloroprene/sulphur copolymer does not ex- ceed about 4 parts by weight per 100 parts by weight of copolymer.

10. Vulcanizable compositions as claimed in claim 5 substantially as herein described.

11. Vulcanizable compositions as claimed in claim 5 substantially as herein described in any of the Examples 1(2), 1(4), 2(3), 3(3), 3(6), 4(1), 4(2), 5(2), 6(2), 6(3), 7(3), 8(2), 8(4), 9(2), 9(3), 9(4), 10(1) and 10(2).

12. A vulcanized polymer having an improved ozone resistance whenever prepared by vulcanization of a composition claimed in any of claims 5 to 11.

13. A vulcanized polymer as claimed in claim 12 substantially as herein described.

14. A vulcanised polymer as claimed in claim 12 substantially as herein described in any of the Examples 1(2), 1(4), 2(3), 3(3), 3(6), 4(1), 4(2), 5(2), 6(2), 6(3), 7(3), 8(2), 8(4), 9(2), 9(3), 9(4), 10(1) and 10(2).

15. A process for the preparation of a vulcanizable composition which comprises incorporating at least one compound claimed in claims 2 to 4 or the composition claimed in claim 1 into a polymer selected from A. chloroprene homopolymers; B. chloroprene/sulfur copolymers; C chlorinated isobutylene/isoprene copolymers; and D. a blend of any of the above polymers A to C with one or more styrene/butadiene copolymers or with natural rubber, the proportion of the polymer A, B or C being at least 50 weight percent of the blend; and the proportion of compound or compositions incorporated being from 0.5 to 5 parts by weight per 100 parts by weight of the polymer or polymer blend.

16. A process as claimed in claim 15 wherein the composition claimed in claim 1 is incorporated into the polymer or polymer blend.

17. A process as claimed in claim 16 wherein a composition as claimed in claim 1 in which tris(5-norbornene-2-methyl) phosphite predominates is incorporated into the polymer or polymer blend.

18. A process as claimed in any of claims 15 to 17 wherein the polymer comprises a chloroprene homopolymer or a chloroprene/ sulfur copolymer.

19. A process as claimed in claim 18 wherein the proportion of sulfur in the chloroprene/ sulfur copolymer does not exceed about 4 parts by weight per 100 parts by weight of copolymer.

20. A process as claimed in claim 15 substantially as herein described.

21. A process as claimed in claim 15 substantially as herein described in any of the Examples 1(2), 1(4), 2(3), 3(3), 3(6), 4(1), 4(2), 5(2), 6(2), 6(3), 7(3), 8(2), 8(4), 9(2), 9(3), 9(4), 10(1) and 10(2).

22. A process for the preparation of a vulcanized polymer which comprises vulcanizing a composition prepared by the process claimed in any of claims 15 to 21.

23. A process as claimed in claim 22 substantially as herein described.

24. A process as claimed in claim 22 substantially as herein described in any of the Examples 1(2), 1(4), 2(3), 3(3), 4(1), 4(2), 5(2), 6(2), 6(3), 7(3), 8(2), 8(4), 9(2), 8(3), 9(4), 10(1) and 10(2).

25. A process for the preparation of the composition claimed in claim 1 substantially as herein described.

26. A process for the preparation of any of the compounds claimed in claims 2 to 4 substantially as herein described.

27. A process for the preparation of the composition defined in claim 1 or any of the compounds claimed in claims 2 to 4 substantially as herein described in any of Examples I to VI.