摘要:
The present invention relates to polyisocyanate-modified dicarboxylic acid derivatives obtainable by reacting organic polyisocyanates with excess quantities, based on the equivalent ratio of NCO/COOH groups, of dicarboxylic acid (poly)anhydrides containing free carboxyl groups and water. The present invention also relates to coating compositions, in particular powder coating compositions, containing these polyisocyanate-modified dicarboxylic acids as curing agents for resins containing epoxy groups.
摘要:
The present invention relates to novel thermoplastic, biodegradable polysaccharide ether esters, such as for example cellulose ether esters or starch ether esters, and to the production of such graft copolymers from polysaccharides, epoxides and dicarboxylic acid anhydrides and to the use thereof, for example as moldings, films or coatings.
摘要:
Disclosed herein is an adhesive and a process for bonding with the adhesive containing an isocyanate prepolymer a), an isocyanate reactive component b) and a catalyst for the reaction of a) and b), characterized in that the catalyst comprises a compound corresponding to the following formula ##STR1## wherein R.sup.1 and R.sup.2 may be identical of different and denote an alkyl group having 1 to 4 carbon atoms,R.sup.3 denotes a CHO group or H or alkyl group having 1 to 4 carbon atoms, optionally substituted with a CHO group,n stands for an integer from 2 to 4,o stands for 1 or 2,p stands for 0 or 1 ando+p=2.
摘要翻译:本文公开了一种粘合剂和与含有异氰酸酯预聚物a),异氰酸酯反应性组分b)和用于a)和b)反应的催化剂的粘合剂的粘合方法,其特征在于催化剂包含对应于 下式“IMAGE”其中R1和R2可以是不同的并且表示具有1至4个碳原子的烷基,R3表示CHO基团或H或具有1至4个碳原子的烷基,任选被CHO基团取代, n表示2〜4的整数,o表示1或2,p表示0或1,o + p = 2。
摘要:
A binder for a coating composition is a combination of(a) polymers containing intramolecular carboxylic anhydride groups and having an average molecular weight of from 500 to 25,000 and(b) organic compounds containing 4,5-dihydrooxazole groups in a quantity corresponding to an equivalent ratio of carboxylic anhydride groups to 4,5-dihydrooxazole groups of from 0.5:1 to 2:1, and contains from 0.005 to 5% by weight, based on the weight of components (a) and (b), of ammonia, a primary amine or secondary amine.
摘要:
The invention relates to a completely biodegradable hydrogel comprising polyester polyurethane polyurea containing urea groups as well as polysaccharides and/or their derivatives, the hydrogel containing plant material capable of dividing. The invention also relates to a process for the embedding of the biological material and the fabrication and shaping of the hydrogels from aqueous solutions. The hydrogels according to the invention may be used as coating material for embedding biological material capable of dividing, especially plant material, preferably plant cells, protoplasts, plant tissues and plant organs, as well as zygotic or somatic plant embryos, under sterile conditions for the purpose of protecting the material during storage, transport and handling. The hydrogels according to the invention may also contain further additives, for example, plant protection agents or nutrients. The embedded biological plant material according to the invention may be used as artificial seed.
摘要:
Free-flowing compression molding compositions made up of from about 40 to about 80 wt. % of organic filler, from about 20 to about 60 wt. % of an organic reactive resin, and optionally further auxiliary substances and additives. The reactive resin contains an epoxide which may be liquid, a latent catalyst and a powdered polyisocyanate which is solid at room temperature.
摘要:
A process for the preparation of a polyurethane-urea elastomer having a mole ratio of NCO groups to all active hydrogen atoms in the range of 0.9 to 1.2 is disclosed. The process comprise reacting (A), (B) and (C.2) for form an NCO-containing prepolymer and then reacting said prepolymer with (C.1) and (D). Accordingly (A) is 5-isocyanato-1-(isocyanatomethyl)-1,1,3-trimethylcyclohexane or bis-(4-isocyanatocyclohexyl)-methane,(B) is polytetrahydrofuran or hexanediol polycarbonate and (C.2) is a chain extender. (C.1) is 5-amino-3-amino-methyl-1,3,3-trimethylcyclohexane or bis-(4-aminocyclohexyl)-methane and (D) is a molecular weight regulator. The elastomer thus produced is particularly suitable for the preparation of moldings, films, flexible tubing (for medical purposes) and catheters.
摘要:
The use of dispersions of urea group-containing polyurethanes based on selected starting materials and crosslinkers leads to the production of fully biodegradable shaped bodies.
摘要:
Reactive systems comprising of a specific polyisocyanate component and a reactive component for this polyisocyanate component, as well as non-reactive plasticizers and if appropriate other auxiliaries and additives, and a process for the preparation of polyurethane plastics containing isocyanurate groups using this reactive system.
摘要:
A hard, resistant material formed by mixing and curinga) at least one polyfunctional silicopolyether,b) at least one monomer which can be subjected to free-radical curing,c) at least one catalyst for polymerization of the free-radical monomers at high temperature, low temperature or under the influence of light, andd) at least one catalyst for the condensation of the silicopolyether.