摘要:
The invention concerns a novel melt-processible poly(ester urethane) and a process and a prepolymer for the preparation thereof. The poly(ester urethane) contains structural units derived from a polyester and structural units derived from a diisocyanate and, according to the invention, the bonds between the structural units are at least mainly comprised of urethane bonds, the number average molar mass, M.sub.n, of the prepolymer is at least 10,000 g/mol, its mass-average molar mass, M.sub.w, is over 20,000 g/mol and its molar mass distribution, expressed as the ratio of M.sub.w /M.sub.n, is over 2, and the prepolymer is essentially free from free isocyanate groups. The poly(ester urethane) is hydrolytically decomposable and it can be used as a biodegradable polymer, e.g., for manufacturing injection molded pieces and thermoformed and blow molded packages, bags, sacks and bottles, for coating of sacks, bags and films made of paper or cardboard, and for manufacturing fibers and non-woven fabrics.
摘要:
The invention concerns a novel melt-processible copolyester and a process and prepolymer for the preparation thereof. The copolyester contains structural units derived from a polyester and structural units derived from diepoxy, and the polyester units at least essentially consist of hydroxy acid monomers. The bonds between the structural units are ester bonds and the number average molar mass, M.sub.n, is at least 10,000 g/mol, its weight average molar mass, M.sub.w, is over 20,000 g/mol and molar mass distribution, expressed as the ratio M.sub.w /M.sub.n, is over 2. The copolyester is hydrolytically degradable and it can be used as a biodegradable polymer for the manufacture of injection moulded articles as well as thermoformed and blow moulded packages, pouches, sacks and bottles, for the coating of sacks bags and films made from paper or cardboard and for the preparation of fibres, fibre cloths and expanded polymer articles.
摘要:
The invention relates to a process for thermoplasticizing starch, a melt-processible polymer composition, which contains a starch-based component and a thermoplastisized polymer component, and a method for preparating such a composition. According to the invention the starch component, which contains hydroxyl groups capable of reacting with isocyanate groups, is modified so that it can be dissolved or gelatinized/plastisized in the melt of a hydroxy acid polymer. The starch component is then reacted with a thermoplastic component formed by a hydroxy acid polymer, in particular a lactic acid polymer, in order to produce a melt-processible, biologically degradable starch-based polymer, which can be used as an adhesive and for coating of paper and cardboard products and for preparation of injection moulded and thermoformed articles.
摘要:
The present invention concerns a procedure for copolymerization of ethylene and alpha olefins with at least eight carbon atoms in the presence of a catalyst of Ziegler-Natta type to become a polymer, in which the quantity of alpha olefin containing at least eight carbon atoms can be regulated between 0.01 and 15% by weight. Polymerization is carried out at a temperature not exceeding 120.degree. C. in a fluid in which the polymer is insoluble. The monomer mixture contains, for increasing the reactivity of the long-chained alpha olefin, 0.01 to 2.0 mol/dm.sup.3 of short-chained alpha olefin with not more than five carbon atoms. The alpha olefin containing not more than five carbon atoms is preferably 1-butylene or propylene.