摘要:
The invention relates to segmented N-alkyl polyurethane amides having an average molecular weight of 5,000 to 250,000, to a process for their production and to their use for the production of materials which may be used in the medical field.
摘要:
Highly heat distortion resistant moulding compositions are disclosed comprising an aromatic polycarbonate having molecular weights Mw (weight average) of a least 10,000, containing bifunctional carbonate structural units corresponding to formula (Ia) ##STR1## wherein R.sup.1 and R.sup.2 denote, independently of one another, hydrogen, halogen, C.sub.1 -C.sub.8 -alkyl, C.sub.5 -C.sub.6 -cycloalkyl, C.sub.6 -C.sub.10 -aryl or C.sub.7 -C.sub.12 -aralkyl,m stands for an integer from 4 to 7,R.sup.3 and R.sup.4, which are selected individually for each X, denote, independently of one another, hydrogen or C.sub.1 -C.sub.6 -alkyl, andX denotes carbonunder the condition that R.sup.3 and R.sup.4 are both alkyl on at least one X atom andas the only thermo stabilizer, from 0.001 to 1% by weight of a siloxane corresponding to formula (II) ##STR2## wherein R and R' denote, independently of one another, C.sub.1 -C.sub.4 -alkyl or -aryl andx and y stand for the numbers 1,2 or 3 and x+y always add up to 4.
摘要:
An improved aqueous coating agent for providing a decorative and protective coating for wood or wood products contains as a binder polyacrylate resins having chemically incorporated therein air-drying, unsaturated fatty acid moieties and quaternary ammonium moieties, and said agent is prepared by reactingA) excess polyacrylates containing epoxide groups and having an epoxide group equivalent weight of 200 to 1,300 withB) drying fatty acids, in an addition reaction with ester formation,C) reacting at least some of the remaining epoxide groups in the A)-B) reaction product with monoamine ammonium salts which contain an N-H bond in an addition reaction, anddissolving the reaction product obtained from step C) and containing quaternary ammonium groups in water.
摘要:
The present invention is directed to an improved process for the direct preparation of polyurethane powders in a finely divided form by the reaction of polyisocyanates and isocyanate reactive compounds in a carrier phase, using interface active compounds, the improvement wherein the interface active compound used consists of at least one polymer of a urethane of (i) a long chain alkyl isocyanate and (ii) a hydroxyalkyl-acrylic or -metacrylic acid ester.
摘要:
Liquid crystalline bis-chlorocarbonic acid esters are 4-hydroxybenzoic acid-(4'-hydroxyphenyl) esters corresponding to the following formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 denote, independently of one another, hydrogen, a halogen atom or a C.sub.1 to C.sub.6 alkyl group. Preparation of (I) and liquid crystalline N-alkyl polyurethanes and polycarbonates prepared form (I) are other invention embodiments.
摘要:
The present invention relates to a process for the preparation of aromatic polycarbonates, aromatic polyester carbonates and aromatic polyesters by the known two phase interface process, which is characterized in that the organic phase used is a mixture of aromatic hydrocarbons with alkanes and/or cycloalkanes.
摘要:
A process for the production of optical fibers based on aromatic polycarbonates wherein the polycarbonate fibres are coated with a plastic, the improvement which comprises(a) to coat the fiber with an UV irradiation-polymerizable mixture which comprises(A) 25 to 75% by weight, based on the total weight of the polymerizable compounds, of a polyfunctional (meth)acrylic acid derivative of the formula ##STR1## (B) 75 to 25% by weight, based on the total weight of the polymerizable compounds, of a monofunctional (meth)acrylate of the formula ##STR2## (C) 0.1 to 10% by weight, based on the total weight of the polymerizable compounds, of a photoinitiator, and(b) to polymerize this mixture on the fibre by UV irradiation.
摘要:
In a test strip for the detection of a component in a liquid sample, the strip comprising a support layer, a microporous polymer layer and a reagent for the detection of the component to be determined, the improvement wherein the microporous polymer layer is a membrane which has an asymmetric pore structure with the narrower pores being on the side to which the sample is applied, and the support layer is macroscopically smooth. The porous membrane is produced by coagulation from solution.
摘要:
In a therapeutic system such as a plaster for administration of an active compound through the skin and comprising a covering layer which is essentially impermeable to the active compound, an active compound reservoir layer and a protective layer which can be pulled off and which is essentially impermeable to the active compound, the improvement wherein the reservoir layer contain about 1-30% of active compound in an elastomer mixture comprising a predominantly amorphous olefinic (co)polymer with a glass transition temperature of