摘要:
The thermoplastic block copolymers according to the invention of optionally substituted vinyl or vinylidene polymer segments and segments of liquid crystalline polymers are suitable for use as compatibility improvers or dispersing agents in otherwise incompatible or poorly compatible thermoplastic polymer mixtures and may be used for the production of moulded articles, filaments, fibres and films.
摘要:
The invention relates to new, free-flowing polyamide molding compounds and blends, characterized in that they are prepared by mixing of polyamides known per se in the melt with low molecular weight, liquid-crystalline esters and/or ester amides corresponding to formula (I) and/or liquid-crystalline, oligomeric esters and/or ester amides corresponding to formula (II) and, optionally, other additives, at least one polymeric blending component being used as a further additive in the case of polyamide blends, and to the use of these liquid-crystalline (LC) additives I and/or II as flow promoters in polyamide molding compounds and blends and to a process for the production of the new polyamide molding compounds and blends. The invention also relates to the new oligomeric esters and/or ester amides corresponding to formula (II).
摘要:
The present invention relates to aromatic compounds corresponding to formula (I) ##STR1## to their production and to their use as modifiers for thermoplastic aromatic polycarbonates and/or thermoplastic aromatic polyester carbonates and/or thermoplastic aromatic polyesters.
摘要:
Thermotropic, fully aromatic polyesters and polyester carbonates are produced by esterification of optionally substituted p-hydroxybenzoic acids and aromatic dicarboxylic acids with diaryl carbonate at temperatures in the range from 100.degree. to 220.degree. C. and subsequent transesterification of the aryl ester obtained with diphenols and, optinally, more diaryl carbonate, accompanied by polycondensation, at temperatures in the range from 250.degree. to 330.degree. C., the esterification, the transesterification and the polycondensation being carried out in the presence of heterocyclic compounds containing 1 to 3 nitrogen atoms.
摘要:
The thermotropic, fully aromatic polycondensates according to the invention, which contain compounds capable of complex formation, are distinguished by improved resistance to hydrolysis and may be used for the production of moulded articles, fibres, filaments, sheet products and films.
摘要:
The liquid crystal polycondensates according to the invention based on aromatic hydroxycarboxylic acids, if appropriate aromatic aminocarboxylic acids, diphenols, if appropriate aminophenols, aromatic dicarboxylic acids and if appropriate carbonic acid which are obtainable by polycondensation of the difunctional monomers mentioned in the melt in the presence of aromatic esters with a defined sequence of the structural units of the formula ##STR1## of oligomers with random distribution of the structural units of the formula ##STR2## have a good heat stability and exhibit a stable viscosity under the processing conditions. The liquid crystal polycondensates can be used for the production of shaped articles, films, fibers and filaments.
摘要:
Thermotropic fully aromatic polyester carbonates containing condensed residues of optionally substituted 3-hydroxybenzoic acid have great rigidity, impact strength and elongation at break and yet can be processed under the usual conditions owing to their advantageous fusion viscosity.
摘要:
Described is a process for producing segmented polyurethanes having improved processing characteristics in the melt state and an efficient spinning process based thereon to form highly elastic, fine linear density elastane yarn and filament having improved mechanical and thermal properties by using hydroxyalkyl-terminated polysiloxanes in combination with specific crosslinking-capable polyisocyanates in the reaction of long-chain high molecular weight polyhydroxy compounds with organic diisocyanates and low molecular weight diols and also optionally further auxiliary and additive substances in the melt.
摘要:
A process for modifying superabsorbent polymers is disclosed. The surface of a polymer containing hydrolyzed polyacrylonitrile in the form of particulates, is modified by crosslinking in a water/alcohol reaction mixture and in the presence of silica. The resulting product features improved absorbency under load and lesser degree of gel blocking.