摘要:
In the case of polyolefins filled with alkaline earth metal carbonates, a very good compatibility of the hydrophilic filler and the hydrophobic polymer matrix is reached when using as adhesion promoters certain organo-phosphorus compounds. As a result, improved mechanical properties are obtained with the articles made of plastic material that has been prepared from such polyolefin molding compositions.
摘要:
In filler-containing molding compositions a very good compatibility between the hydrophilic filler and the hydrophobic polymer matrix is obtained by using as adhesion promotor alkali metal salts of alkyl or alkylene-sulfonic acids or alkyl sulfates, the derivatives thereof and the acids on which the salts are based. The flow properties of the molding compositions and the mechanical properties of the shaped articles made therefrom are improved.
摘要:
In filler-containing plastic molding compositions based on polyoxymethylene, very good compatibility between the filler and the polymer matrix is obtained when alkali metal or alkaline earth metal salts of certain sulfonic acids or alkylsulfuric acids are used as adhesion promoters. The result is that in particular the flow properties of the molding compositions and mechanical properties of the plastic articles prepared therefrom as well as the color properties are improved.
摘要:
The invention provides thermoplastic molding compositions having improved properties. The compositions are composed of a mixture of from 99.999 to 99.9 wt.% of a linear polyoxymethylene and from 0.001 to 0.1 wt.% of a branched or cross-linked copolymer of trioxan with a multifunctionally reacting compound and optionally a monofunctionally reacting compound, or with a monofunctionally reacting compound and a branched or cross-linked polyether, or of a subsequently branched or cross-linked linear polyoxymethylene having functional groups in lateral or chain position.
摘要:
Oxymethylene polymers (POM) are obtained in granular form by cooling a POM solution or dispersion having a temperature above the sintering temperature of the POM in two stages to a temperature just below the said sintering temperature. The solvent or dispersion agent used is a mixture of methanol and water and the cooling agent is a methanol/water mixture which may contain POM suspended therein. The granular POM obtained is suitable as technical material for making shaped articles.
摘要:
Branched or crosslinked poly(exymethylenes) are suitable as nucleating agents for linear poly(oxymethylenes). For ameliorating the mechanical properties of shaped articles, being prepared of such moulding compositions which contain nucleating agents, high molecular weight polymers are used having a certain softening point, second order transition temperature and particle size, and which are blended into the moulding compositions. The modified moulding compositions can be processed in the thermoplastic state and are suitable as industrially useful materials for preparing semi-finished articles and finished products.
摘要:
Silicate catalysts which can be employed for selective oxidation reactions of organic substances, a process for the preparation of these catalysts and their use are described.The catalyst is distinguished by high long-term activity, by the reaction temperature required for the reaction being lower in comparison with catalysts composed of pure silver and by higher conversions and selectivities in the oxidative dehydrogenation of alkanols in comparison with pure silver or silver on supports.
摘要:
The process dehydrogenates methanol in the presence of a catalyst based on aluminum oxide, alkali metal aluminate and/or alkaline earth metal aluminate with the exclusion of oxygen at a temperature of 650.degree. to 1050.degree. C. in a reactor whose inner wall is composed entirely or partly of aluminum oxide. The process gives anhydrous formaldehyde which contains only very minor impurities.
摘要:
The invention relates to a process for obtaining trioxane from aqueous solutions by high-pressure extraction using an extracting agent which is in the form either of a gas in the supercritical state or of a liquid gas. An intermediate separation is advantageous, especially in the former case.The trioxane can be obtained in high concentration and with a saving of energy by the process according to the invention.
摘要:
A thermoplastic molding composition being a suitable material for technical purposes comprises a mixture of an oxymethylene polymer and of an elastomeric copolyester having short-chain and long-chain diol elements as well. The molding composition is prepared by mixing and homogenizing the components and may contain usual additives, especially stabilizers.