摘要:
The invention relates to a process for determining a molecular weight distribution in a polymer. When a polymer is prepared, chains of different length are formed. Correspondingly, a distribution of the molecular weights of the chains of a polymer arises.It is an object of the invention to be able to determine the molecular weight distribution in an improved manner compared to the prior art.The object of the invention is achieved by describing starting data G*(ω) available in numerical form, i.e. the complex shear modulus measured as a function of frequency or the mastercurve constructed therefrom, are described by an analytical function. In this way, exact knowledge of the relaxation behaviour is available in improved form, in particular also in the case of prolonged relaxation times. This enables a valid determination of the relaxation time spectrum and hence a fundamentally more valid calculation of the molecular weight distribution.
摘要:
The invention relates to a process for determining a molecular weight distribution in a polymer. When a polymer is prepared, chains of different length are formed. Correspondingly, a distribution of the molecular weights of the chains of a polymer arises.It is an object of the invention to be able to determine the molecular weight distribution in an improved manner compared to the prior art.The object of the invention is achieved by describing starting data G*(ω) available in numerical form, i.e. the complex shear modulus measured as a function of frequency or the mastercurve constructed therefrom, are described by an analytical function. In this way, exact knowledge of the relaxation behaviour is available in improved form, in particular also in the case of prolonged relaxation times. This enables a valid determination of the relaxation time spectrum and hence a fundamentally more valid calculation of the molecular weight distribution.
摘要:
A novel vulcanizable composition is provided, based on at least one hydrogenated nitrile rubber, on at least one peroxide, on at least one unsaturated carboxylic acid and/or salts thereof, and also on specific microgels. These vulcanizable compositions can be used to obtain vulcanized products which can in particular be used for drive belts, roll coverings, hoses and cables.
摘要:
Novel crosslinkable compositions based on elastomers, at least one of which has carboxyl and/or carboxylate groups, are provided, these crosslinkable compositions containing special unsaturated organic salts of metal ions and a crosslinking system which acts as a free radical donor. Crosslinked elastomers which have excellent physical properties are obtainable therefrom. The novel crosslinkable compositions have a wide range of uses.
摘要:
Novel crosslinkable compositions are provided and are based on thermoplastic polymers and elastomers, these compositions comprising, as crosslinking system, specific organic salts of metal ions. Ionically crosslinked thermoplastic elastomers can be obtained therefrom and have excellent physical properties, high-temperature resistance extending above 150° C., and also oil resistance. They can be used for production of moldings.
摘要:
Novel crosslinkable compositions are provided and are based on thermoplastic polymers and elastomers, these compositions comprising, as crosslinking system, specific organic salts of metal ions. Ionically crosslinked thermoplastic elastomers can be obtained therefrom and have excellent physical properties, high-temperature resistance extending above 150° C., and also oil resistance. They can be used for production of mouldings.
摘要:
Novel crosslinkable compositions based on elastomers, at least one of which has carboxyl and/or carboxylate groups, are provided, these crosslinkable compositions containing special unsaturated organic salts of metal ions and a crosslinking system which acts as a free radical donor. Crosslinked elastomers which have excellent physical properties are obtainable therefrom. The novel crosslinkable compositions have a wide range of uses.
摘要:
A novel vulcanizable composition is provided, based on at least one hydrogenated nitrile rubber, on at least one peroxide, on at least one unsaturated carboxylic acid and/or salts thereof, and also on specific microgels. These vulcanizable compositions can be used to obtain vulcanized products which can in particular be used for drive belts, roll coverings, hoses and cables.
摘要:
The present invention relates to highly branched and coupled polymers based on conjugated dienes or on conjugated dienes and vinylaromatic compounds and on polyfunctional, organic compounds with at least four groups which are capable of coupling. Vulcanization products and shaped rubber articles of all types, in particular tires having an improved rolling resistance, can be produced from the highly branched diene polymers according to the present invention.
摘要:
The present invention relates to a single- or multilayer product containing &agr;-olefin-vinyl alcohol copolymers and at least one &agr;-olefin-vinyl acetate copolymer, wherein the amount of vinyl acetate repeat units present in the &agr;-olefin vinyl acetate copolymer is in the range from 35 to 99.99% by weight, and these repeat units have good flexibility which permits processing films or other thin-walled items which are transparent after stretching or thermoforming, and to a process for producing the same, and to their use as packaging films.