摘要:
Novel elastomer/oxymethylene polymer blends are disclosed whose impact strength or resistance has been enhanced, with no appreciable diminution in their outer useful properties, by the inclusion therein of a novel elastomer/oxymethylene graft copolymer compatibilizing agent prepared by grafting polyformaldehyde or oxymethylene copolymer chains onto a halogenated elastomeric polymer by means of a reaction initiated at graft sites, i.e., at the sites of the haloelastomer's halo substituents, using, e.g., an initiated site-forming cationic salt.
摘要:
Low Tg copolymers of trioxane and 1,3-dioxolane which have a dioxolane content greater than 65 mol percent and less than about 75 mol percent and an IV of from about 1.0 to about 2.3, and which are non-crystalline at room temperature or above, are disclosed. These polymers, when blended with crystalline oxymethylene polymers, improve the latter's impact properties. They can also be used as adhesives for crystalline oxymethylene polymers.
摘要:
Crosslinked elastomeric acetal polymers are made by the copolymerization of 1,3-dioxolane with a smaller amount of one or more bifunctional monomers. The two functional groups of the bifunctional monomer react under the same cationic polymerization conditions as the 1,3-dioxolane. The elastomeric acetal polymer does not crystallize even when the temperature is as low as -50.degree. C. The elastomeric acetal polymer is particularly useful for blending with crystalline acetal polymers to yield a composition with improved impact resistance.
摘要:
Ultraviolet curable terpolymers of trioxane, from at least 65 weight percent to about 75 weight percent of 1,3-dioxolane and from about 2 weight percent to about 20 weight percent of a monoethylenically unsaturated aliphatic diol formal having at least 4 carbon atoms in its main chain, e.g., 4,7-dehydro- 1,3-dioxepin, which are non-crystalline at room temperature or above are disclosed. These terpolymers, when admixed with a multifunctional crosslinking monomer, e.g., a multifunctional acrylate such as 1,6-hexanediol diacrylate, and a photosensitizer, e.g., a benzoin compound such as benzoin isobutyl ether, can be cured to an insoluble, non-tacky, rubbery state using UV radiation. The thus-cured polymeric materials form useful crosslinked films, and when cryogenically ground to a suitable small particle size can be blended with conventionally prepared crystalline oxymethylene homo-, co- and terpolymers to improve the latters' impact properties.
摘要:
There are provided novel mixtures and composites comprising a normally crystalline acetal polymer and a reinforcing material comprising glass fibers or filaments sized with a normally non-crystalline elastomeric copolymer of about 15 to 45 mol %, preferably about 25 to 35 mol % of trioxane, about 55 to 85 mol %, preferably about 65 to 75 mol % of 1,3-dioxolane, said mol percents based on the total of trioxane and 1,3-dioxolane, and about 0.005 to 0.15 wt. %, preferably about 0.05 to 0.12 wt. % of 1,4-butanediol diglycidyl ether or butadiene diepoxide as a bifunctional monomer, based on the total weight of copolymer.
摘要:
There are provided new moldable blends of a normally crystalline acetal polymer and a normally non-crystalline elastomeric copolymer of about 15 to 45 mol %, preferably about 25 to 35 mol % of trioxane, about 55 to 85 %, preferably about 65 to 75 mol % of 1,3-dioxolane, said mol percents based on the total of trioxane and 1,3-dioxolane, and about 0.005 to 0.15 wt. %, preferably about 0.05 to 0.12 wt. % of 1,4-butanediol diglycidyl ether or butadiene diepoxide as a bifunctional monomer, based on the total weight of copolymer.
摘要:
Oxymethylene polymer bonded articles, such as multilayer laminates, are disclosed. Such articles are prepared by bonding together at least two articles shaped or molded from crystalline oxymethylene homo-, co- and terpolymers using, as an adhesive, a low Tg copolymer of trioxane and 1,3-dioxolane which have a dioxolane content greater than 65 mol percent and less than about 75 mol percent and an IV of from about 1.0 to about 2.3, and which are non-crystalline at room temperature or above.
摘要:
A bio-degradeable seed coating composition for enhanced seed protection and propagation comprises a gelatin-based hydrogel formulation consisting of a naturally derived, hydrophilic protein in combination with a sulfated or non-sulfated polysaccharide. The protein is animal porcine or bovine derived while the polysaccharide is preferably a cellulose derivative such as sodium cellulose sulfate, dextran sulfate, sulfated chitosan, sulfated starch and mixtures thereof. The seed coating composition may also comprise a rheology modifier comprising a clay, a dessicant or silica gel.
摘要:
Non-crystalline elastomeric acetal polymers are disclosed which have ethylenic unsaturation in the polymer backbone. The polymers are synthesized by the ring-opening polymerization of 1,3-dioxolane, 1,3-dioxepane, and the cyclic formal of an ethylenically unsaturated diol having at least 4 adjacent carbon atoms in its main chain. The preferred cyclic formal is 4,7-dihydro-1,3-dioxepin. Because of the ethylenic unsaturation, the elastomeric acetal polymers can be vulcanized or cured with multifunctional vinyl monomers to produce elastomers with improved properties, such as better elasticity, decreased thermoplasticity and decreased solubility. The elastomeric acetals in any of their embodiments are particularly useful for blending with crystalline acetal polymers to improve the impact resistance of the crystalline acetal polymers.
摘要:
A crosslinked elastomeric acetal polymer is synthesized from 1,3-dioxolane, 1,3-dioxepane, and a polyfunctional crosslinking compound having two or more functional groups that react under conditions of cationic polymerization, such as 1,4-divinyloxybutane or poly(butadiene oxide). The polymers are elastomeric and non-crystalline at temperatures well below room temperature. They can be blended with crystalline acetal polymers to produce blends that have improved impact properties.