Motor vehicle recovery spurs growth of specialty elastomers and TPEs.

A recovery in the once-struggling motor vehicle markets should fuel modest increases in demand for specialty elastomers and thermoplastic elastomers through 1996, according to market research firm, The Freedonia Group.

Due to a recovery in light vehicle production from depressed 1991 levels, world specialty elastomer production is expected to increase 3.3% annually to two million metric tons in 1996. However, the total growth in specialty elastomers will lag that of light vehicle production.

Two main factors will account for this slower growth:

* the displacement of high volume specialty elastomers by competitive materials; and

* the continuing downsizing of automobiles - thus reducing the amount of rubber required per vehicle.

Low volume elastomers, on the other hand, are benefiting from increased use in automobiles, and growth will significantly outpace that of light vehicle production.

Geographic growth areas

Capacity for specialty elastomers continues to be almost entirely dominated by North America, Western Europe and Japan. These regions should continue to dominate the industry over the forecast period due to both high capital costs and the highly specialized nature of most specialty elastomers.

Latin America and the Pacific Rim have significantly increased rubber capacity over the last decade, but almost all of this has been for commodity rubbers such as SBR and BR.

High volume elastomers

High volume specialty elastomers such as ethylene-propylene, butyl, polychloroprene and nitrile should see increased world production at a rate of 3.1% per year, to 1.8 million metric tons in 1996.

Increased light vehicle production should benefit this growth, but a considerable degree of displacement, occurring at the hands of more advanced polymers, such as fluoroelastomers, will restrain greater gains, especially for polychloroprene. Most favorable growth is expected from EPM/EPDM, which, despite displacement in some applications, will see good growth in thermoplastic elastomers and in roofing systems.

Low volume elastomers

World production of low volume specialty elastomers, encompassing silicone elastomers, acrylic rubber, fluoroelastomers, epichlorohydrin elastomers, sulphide polymers and polynorbornene rubber, is forecast to increase 5.5% per year to 170,000 metric tons in 1996. Fastest annual gains will be found in acrylic rubber and fluoroelastomers, although silicone elastomer will remain the largest volume elastomer in this class. Much of this growth relies heavily on continuing strong demand from the automotive industry, where low volume specialty elastomers are used in gaskets, seals, hoses and belting.

TPEs

The recovery of the large motor vehicle market and rapid gains in smaller markets such as appliances, medical products and construction products are expected to increase North American demand for thermoplastic elastomers 5.9% per year through 1997. TPEs' gains will continue to come primarily at the expense of thermoset rubber, although TPEs will also displace rigid thermoplastics, especially PVC, as well as various metals.

Growth by type

Styrenic TPEs account for the greatest volume of the TPE market due to their excellent properties (e.g., recyclability, weatherability and tensile strength) and versatility. Despite strong growth in markets such as motor vehicles and industrial products, analysts expect styrenic TPE growth to lag the industry average as a result of continuing weakness in footwear markets, the largest volume outlet for these materials.

Olefins and polyesters will see the most rapid growth of all TPEs. Thermoplastic olefins, or TPOs, will see extremely favorable growth of 8.7% annually due to expanding applications in motor vehicles for such exterior parts as bumpers, bumper panels and parts, grills, airdams and exterior body panels. Copolyester elastomers (COPE) will see the highest gains, 8.9% annually, caused by continued growth in the large industrial products markets, and gains in medical and appliance uses.

Major markets for TPEs in North America are motor vehicles and other transporation equipment, industrial products and footwear.

Rubber composition U.S. patent: 5,179,156 Issued: January 12, 1993 Inventors: Hiroyoshi Takao, Hiroyuki Harada, Kiyoyuki Sugimori, Nobuyuki Yoshida, Masabiro Fukuyama, Hideaki Yamada, and Junichi Koshiba Assigned: Sumitomo Chemical Co.

A vulcanizable rubber composition comprising a copolymer rubber constituted of ethylene, propylene and 5-ethylidene-2-norbornene and/or dicyclopentadiene, wherein ethylene/ propylene molar ratio is 86/14 to 97/3, wherein the ratio of the contents of the ingredients (A) is defined by the following equation:

A = 42P + 120D/42P + 120D + 28E

wherein each of P, D and E represents the content (% by mole) of propylene, 5-ethylidene-2-norbornene and/or dicyclopentadiene and ethylene, respectively.

Process for producing a thermoplastic elastomer composition U.S. patent: 5,180,769 Issued: January 19, 1993 Inventors: T. Hikasa, K. Ibuki, T. Hamanaka and M. Mizumori Assigned: Sumitomo Chemical Co.

A process for producing an olefinic thermoplastic elastomer composition which comprises partially crosslinking a mixture comprising (A) 40-95% by weight of an oil-extended olefinic copolymer rubber obtained by adding 20-150 parts by weight of a mineral oil to a solution of 100 parts by weight of an olefinic copolymer rubber having Mooney viscosity ([ML.sub.1-4] 100 [degrees] C) Of 170-350 and (B) 5-60% by weight of an olefinic plastic in the presence of an organic peroxide.

Rubber-modified nylon composition U.S. patent: 5,180,777 Issued: January 19, 1993 Inventors: Allen R. Padwa, Richard E. Lavengood and Raman Patel Assigned: Monsanto Company A polymer blend consisting essentially of:

(A) a core/shell graft rubber copolymer comprising of a rubber core of polybutadiene or a butadiene copolymer and a thermoplastic copolymer shell comprising styrene, a polar monomer selected from the group consisting of (meth)acrylonitrile and methyl (meth)-acrylate and acrylamide,

(B) a polyamide; and a terpolymer rubber of an a-olefin, a [C.sub.1] to [C.sub.4] alkyl acrylate and an acid-containing monomer, having a glass transition temperature below 0 [degrees] C.

Process for the production of alloys of rubber and aromatic polyesters U.S. patent: 5,180,781 Issued: January 19, 1993 Inventors: Holger Lutjens, Uwe Westeppe,, Karl-Erwin Piejko, Bergisch Gladbach and Christian Lindner Assigned: Bayer Aktiengesellschaft

A process for the production of an alloy of cross-linked or partially cross-linked rubbers and aromatic polyesters, wherein a mixture of a rubber latex and an aqueous solution of an alkali metal diphenolate or an alkaline earth metal diphenolate is reacted with a solution of a dicarboxylic acid halide and/or a carbonyl halide in a water-immiscible solvent, an aromatic polyester forming at the phase boundary of water/organic solvent, which polyester goes over into the organic phase, and the rubber at the same time going from the aqueous phase into the organic phase, and the organic phase is then separated and the organic solvent is removed.

Pneumatic tire having expanded outer tread rubber layer U.S. patent: 5,181,976 Issued: January 26, 1993 Inventors: S. Iwafune, K. Yamaguchi, E. Takiguchi and T. Iwata Assigned: Bridgestone Corp.

A pneumatic tire comprising: a tire casing, a tread covering a crown portion of said casing, said tread consisting of an outer layer portion comprised of an expanded rubber layer having a volume corresponding to at least 10% of a total volume of said tread and a non-expanded rubber inner layer portion.

Ozone-resistant butyl elastomer U.S. patent: 5,182,350 Issued: January 26, 1993 Inventors: James V. Fusco, Hsien-Chang Wang and Kenneth W. Powers Assigned: Exxon Chemical

A vulcanizable copolymer of at least one isoolefin and at least one nonconjugated diene of the formula

               CH3
               /

[H.sub.2]C = C - [R.sub.1] - [R.sub.2] where [R.sub.1] is a member of the group consisting of

             CH3
             /

- alkylene - CH = C-,

             [CH.sub.3]
             /

- alkylene - C = UH - and

And [R.sub.2] is a [C.sub.1] to [C.sub.6] alkyl group, said copolymer containing about 85 to 99.5 weight percent of said at least one isoolefin moiety.