摘要:
The present invention relates to a process for the preparation of carbonic acid esters of polyester-polyols by transesterifying the polyols with carbonic acid aryl esters at elevated temperatures under vacuum in the presence of a catalyst. The reaction conditions are controlled to avoid the formation of by-products and the chain extension of the polyester-polyols. The present invention is also concerned with the polyester carbonic acid esters so formed, their use in producing polycarbonate block copolymers and the copolymers so produced. The copolymers may be produced by transesterifying the polyester carbonic acid esters with bisphenols and subjecting the bis-hydroxyaryl carbonates so formed to normal polycarbonate synthesis such as interfacial or melt polycondensation.
摘要:
The present invention relates to polycondensates of the formula 10, their use for absorbing metal ions of the transition elements of the periodic system and their use for the preparation of polymers containing metals of formula 11 which have e.g. improved resistance to heat and to chemicals compared to the corresponding polycondensates of formula 10.
摘要:
The sensitivity of silver halide emulsions is increased if the silver halide is precipitated in the presence of a peptization agent which consists partially or wholly of a copolymer comprising 0.1 to 20 mol% of recurring structural units of the formula ##STR1## in which X is hydrogen or alkyl having 1 to 4 carbon atoms and Y is a 8-hydroxyquinoline group attached through its 5- or 7-position.
摘要:
Homo- and copolymers of monomers obtained by acylation of 2-[4-hydroxy(or amino)phenyl]-2-[5-(8-hydroxyquinolyl)]-propane with .alpha.,.beta.-monoolefinically unsaturated carboxylic acid halides or - anhydrides. As comonomers can be employed compounds containing one or more .alpha.,.beta.-olefinically unsaturated groups such as olefines, diolefines, acrylic acid derivatives, vinyl monomers. The polymers having molecular weights between 5000 - 500,000 can be prepared by radical or ionic chain mechanisms, in continuous or discontinuous processes. They may be used for removing metal ions from their solution, for complexing of interfering metallic impurities in thermoplastic or thermosetting resins or in form of their metal complexes as stabilizers for plastics.
摘要:
Insoluble polyphosphonates produced via a transesterification process, methods for preparing such insoluble polyphosphonates and polymer compositions and articles of manufacture including such insoluble polyphosphonates are described herein.
摘要:
Disclosed are oligomeric phosphonates including oligophosphonates, random or block co-oligo(phosphonate ester)s and co-oligo(phosphonate carbonate)s produced using a condensation process terminated with hydroxyl, epoxy, vinyl, vinyl ester, isopropenyl, isocyanate groups, and the like. These materials can be used as a reactive additive to other polymers, oligomers or monomer mixtures to impart flame resistance without diminishing melt processability which is important in the fabrication of polymers for many applications.
摘要:
Disclosed is a new method and compositions from the method consisting of block copolycarbonate/phosphonates that exhibit an excellent combination of flame resistance, hydrolytic stability, high Tg, low melt viscosity, low color and high toughness. Also disclosed are polymer mixtures or blends comprised of these block copolycarbonate/phosphonate compositions and commodity and engineering plastics and articles produced therefrom. Further disclosed are articles of manufacture produced from these materials, such as fibers, films, coated substrates, moldings, foams, adhesives and fiber-reinforced articles, or any combination thereof.
摘要:
A method for preparing substantially pure optionally substituted diaryl alkylphosphonates from an optionally substituted triarylphosphite and an optionally substituted trialkylphosphite or an optionally substituted alkanol under special reaction conditions is described.
摘要:
Disclosed are crystalline polyphosphonates and a method to induce crystallization. These crystalline polyphosphonates exhibit a unique and advantageous combination of properties, allowing for solid state post polymerization reactions and solid state dry mixing with other polymers. Also disclosed are polymer compositions that comprise these polyphosphonates and at least one other polymer, wherein the resulting polymer compositions exhibit flame retardant properties. Further disclosed are articles of manufacture produced from these crystalline polyphosphonates and polymer compositions, such as fibers, films, coated substrates, moldings, foams, fiber-reinforced articles, or any combination thereof.
摘要:
Disclosed are linear polyphosphonates produced by a transesterification process. These linear polyphosphonates exhibit a unique and advantageous combination of properties, such as outstanding fire resistance, unexpectedly high Tg's and good toughness at a low molecular weight. The favorable processing characteristics (such as low melt viscosity and excellent melt stability) of these linear polyphosphonates enable economic processing. Also disclosed are polymer compositions that comprise these linear polyphosphonates and at least one other polymer, wherein the resulting polymer compositions exhibit flame retardant properties.