摘要:
A flame retarded, injection moldable, saturated, linear polyester composition contains red phosphorus as flame retardant and a metal iodide as phosphine suppressing agent. The metal is one of the groups 1a and 2b of the periodic table of elements with potassium iodide being the most preferred.The phosphine evolution of a poly(ethylene terephthalate) molding composition containing 4% red phosphorus as flame retardant is reduced to 0.3 ppm at the die and to 1.0 ppm in storage by the addition of 0.6% of potassium iodide.
摘要:
A process for decreasing the melt index and increasing the viscosity of polyamide compositions by adding thereto an effective amount of an aryl phosphate compound, and thereafter heating the composition until the desired changes in melt index or viscosity are attained.
摘要:
A process for rapidly and substantially decreasing the melt index and increasing the viscosity of polymers of caprolactams during melt processing by forming a molten mixture of the polymer and a phosphite compound and heating the mixture until the desired change in melt index and viscosity are obtained.
摘要:
A process for preparing quasi-random copolymers is described which involves heating a mixture of polyamides in the presence of one or more phosphite promotor(s). The process is conducted at temperatures between about 265.degree. C. and 315.degree. C. with the process time generally ranging from about 2 to about 20 minutes. The process is especially useful for preparing copolymers from a mixture of poly(caproamide) and poly(hexamethylene adipamide). The copolymer products prepared in accordance with the process are particularly suitable for the production of plastic films which have improved properties as compared to either of the homopolymers.
摘要:
A process for preparing block, and/or graft copolymeric compositions by forming an intimate mixture of two or more polymers, at least one of which includes one or more amino junctions and at least one of the remaining polymers includes one or more carboxylic acid junctions and an effective amount of a phosphite compound, and thereafter heating the intimate mixture at a temperature and for a time sufficient to form the desired block, and/or graft copolymers.
摘要:
Nerve channels made from high molecular weight lactic acid polymers, preferably polymers having a molecular weight between about 234,000 and 320,000, provide an unexpectedly beneficial effect on cell growth and regeneration of function.
摘要:
Crimped foamed fibers are produced by a process which eliminates any mechanical deformation steps. The process comprises the step of forming foamed fibers having a plurality of randomly arranged cells distributed asymetrically over a given cross section and occupying at least about 10% of the cross sectional area of the fiber, and heating the foamed fibers while maintaining the fibers under no load condition to produce a crimped foamed fiber. The crimped foamed fibers are used in apparel, carpet fibers, thermal insulation, acoustic and filtration.
摘要:
This invention relates to an implantable medical device capable of encouraging cellular growth and regeneration of function fabricated totally or in part from one or more bioresorbable polymers, as for example bioresorbable homopolymers derived from the polymerization of alpha-hydroxy carboxylic acids, where at least one of the polymers has an average molecular weight of from about 234,000 to about 320,000 as measured by gel permeation chromatography.
摘要:
This invention relates to a fiber comprising a major amount of a continous phase comprising one or more melt processible polyesters of fiber forming molecular weight, and a minor amount of one or more polyolefins non-uniformly dispersed in said continuous phase such that the concentration of polyolefins at or near the surface of said fiber is greater than the concentration of polyesters at or near the surface of said fiber, and a process for preparing said fiber.
摘要:
This invention relates to fire retarded polymeric composition comprising a polymeric material, red phosphorus and a phosphine suppressant which is a copper salt.