摘要:
A laminate comprising a thermoplastic polymer essentially consisting of polylactic acid, a copolymer of lactic acid and hydroxycarboxylic acid or a mixture of polylactic acid with a copolymer of lactic acid and hydroxycarboxylic acid, and a regenerated cellulose film, paper, leather, cloth, or fiber. The laminate undergoes degradability in the natural environment, is excellent in transparency, gloss and moisture-proofness, has high strength and can be used for various packaging materials.
摘要:
A breathable, hydrolyzable, porous film which is obtained by the process comprising adding from 40 to 250 parts by weight of a finely-powdered filler having an average particle size of from 0.3 to 4 .mu.m to 100 parts by weight of a polylactic acid-based resin composition comprising from 80 to 100% by weight of polylactic acid or a lactic acid-hydroxycarboxylic acid copolymer and from 0 to 20% by weight of a plasticizer, melting and film-forming the resultant mixture, and successively stretching the thus-obtained film 1.1 times or more at least in the direction of the axis; and which is consequently useful as a material for leakproof films of sanitary materials such as a paper diaper and packaging materials, and does not accumulate as wastes because of hydrolyzability in the natural environment in the case of being abandoned after use.
摘要:
A modified polyolefin resin comprising a copolymer having a structure that a propylene-based polyolefin segment (a) and a segment (b) containing a lactic acid as a constituent are bonded in a block state and/or a graft state through a vinyl monomer having a hydroxyl group, wherein a number average molecular weight of the propylene-based polyolefin segment (a) is from 1,000 to 100,000, a number average molecular weight of the segment (b) containing lactic acid as a constituent is from 1,000 to 200,000, and a weight composition of the propylene-based polyolefin segment (a) and the segment (b) containing lactic acid as a constituent is from 10/90 to 90/10. The modified polyolefin resin can be used in a resin composition containing an aliphatic polyester resin (A), a polyolefin resin (B) and the modified polyolefin resin (C). The composition can exhibit excellent heat resistance and impact resistance and can be used for molding various parts.
摘要:
A resin composition (AA) comprising an aliphatic polyester or aliphatic polyamide (component (A)), a plastic having a melting point or glass transition temperature (Tg) of −10° C. or more (component (B)) and a radical generating agent (C), wherein the compounding ratio of the component (A), the component (B) and the radical generating agent (C), based on the total weight thereof, is: 1 to 98.995% by weight of the component (A), 98.995 to 1% by weight of the component (B), and 0.005 to 5% by weight of the radical generating agent (C), and an aliphatic unsaturated polybasic acid (a) is contained in the polymer constituent of the component (A) and/or the component (B). The resin composition is suitable as a starting material of biodegradable material which maintains transparency, is free of bleeding of a plasticizer, is endowed with flexibility and has other advantageous characteristics so that it can be used in various fields.
摘要:
A sustained releasing drug which includes an effective component and a copolymer having a weight-average molecular weight of 1,000 to 100,000 which comprises, as repeating structure units, both of a succinimide unit represented by the structural formula (1) and a hydroxycarboxylic acid unit represented by the structural formula (2) wherein R is a methyl group or a hydrogen atom, and a process for preparing a copolymer which comprises a polymerization step of heating a mixture of aspartic acid and a cyclic ester compound.
摘要:
A degradable polymer composition essentially consisting of a mixture of a thermoplastic polymer composition primarily comprising polylactic acid or lactic acid-hydroxycarboxylic acid copolymer and one or more substance selected from starch and modified starch, and is a degradable polymer which does not cause problems such as environmental pollution and can be used for films, filaments and packaging materials, food packaging materials in particular.
摘要:
The present invention provides a nylon composition having increased hydrolyzability which is obtained by physically mixing 100 parts by weight of a nylon with 1 to 50 parts by weight of at least one polymer selected from the group consisting of polylactic acid, polyglycolic acid and a copolymer containing 50 mol % or more of a lactic acid unit or a glycolic acid unit as a repeating unit in its chain; and a method for increasing the hydrolyzability of a nylon by preparing such a composition. High hydrolyzability can be imparted to the nylon inherently having extremely low hydrolyzability without impairing its original mechanical strength. Therefore, various molded articles made from the nylon can be hydrolyzed under natural circumstances, and thus the wastes are not stored.
摘要:
A degradable polymer network obtained by adding from 0.2 to 10 parts by weight of a foaming agent to 100 parts by weight of a polylactic acid-base resin composition comprising from 80 to 100% by weight of polylactic acid or a lactic acid-hydroxycarboxylic acid copolymer and from 0 to 20% by weight of a plasticizer, conducting melt-foaming extrusion of resulting mixture, and opening the foam cells in the extrudate. The high polymer network is characterized in suitable flexibility and hydrolyzability and thus useful as a material for absorbing of oils and body fluids, screens for sunlight, heat-insulating materials, filter media and packaging materials; and does not accumulate as industrial wastes because of hydrolyzability in the natural environment, even though abandoned after use.
摘要:
A styrene derivative carrying N-acethylchito-oligosaccharide chains, a polystyrene derivative carrying N-acetylchito-oligosaccharide chains on the side chains as well as a method for preparing these compounds are herein disclosed. The method for preparing the styrene derivative comprises reacting N-acetylchito-oligosaccharide lactone with vinylbenzylamine or a derivative thereof while the method for preparing the polystyrene derivative comprises polymerizing the styrene derivative. These derivatives can be employed as biomedical materials, in particular as materials for cell culture.