摘要:
A resin powder for solid freeform fabrication has a 50 percent cumulative volume particle diameter of from 5 to 100 μm and a ratio (Mv/Mn) of a volume average particle diameter (Mv) to the number average particle diameter (Mn) of 2.50 or less and satisfies at least one of the following conditions (1) to (3): (1): Tmf1>Tmf2 and (Tmf1−Tmf2)≧3 degrees C., both Tmf1 and Tmf2 are measured in differential scanning calorimetry measuring according to ISO 3146, (2): Cd1>Cd2 and (Cd1−Cd2)≧3 percent, both Cd1 and Cd2 are measured in differential scanning calorimetry measuring according to ISO 3146, and (3): C×1>C×2 and (C1−C2)≧3 percent.
摘要:
The present invention provides cyclic dimers of alpha acids and polymers derived therefrom. Also provided are processes for preparing and methods of using the cyclic dimers and the polymers derived from the cyclic dimers.
摘要:
The invention relates to functionalized polymers including homopolymers and copolymers and their uses in industrial applications and in agricultural applications. In particular, the homopolymers and copolymers may be, for example, used in polymer blends, used as nutritives and in feed compositions, and used in combination with a pharmaceutical or nutritive.
摘要:
The present invention relates generally to substrates for making polymers and methods for making polymers. The present invention also relates generally to polymers and devices comprising the same.
摘要:
A method of producing a material comprising nanocellulose and a polymer, comprising carrying out in-situ, ring opening of polymerisation of dry nanocellulose dispersed in a monomer to produce said material. The material can be used as a reinforcing additive for plastics, for example in the form of a plastics masterbatch.
摘要:
Aromatic oligomers, in particular arylene ketone and arylene sulfone oligomers, are prepared by reacting an appropriate monomer system in the presence of free Lewis acid and a complex between a Lewis acid, for example, aluminum trichloride, and a Lewis base, for example, N,N-dimethylformamide, and, optionally, a diluent, such as methylene chloride. The process is particularly advantageous for the preparation of substantially or all paralinked arylene ether ketone oligomers as the presence of the Lewis acid/Lewis base complex markedly reduces alkylation and ensures the substantial absence of ortho substitution. The monomer system can be, for example, a self-reacting monomer such as p-phenoxy-benzoyl chloride or a two-monomer system such as 1,4-diphenoxybenzene and terephthaloyl chloride.
摘要:
The invention is a process for preparing linear alternating polymers of sulfur dioxide, ethylene, optionally at least one ethylenically unsaturated hydrocarbon other than ethylene and optionally carbon monoxide having the general formula ##STR1## wherein Z is at least one moiety selected from SO.sub.2 and CO, G is the moiety of at least one ethylenically unsaturated hydrocarbon of at least 2 carbon atoms polymerized through the ethylenic unsaturation, n is an integer of at least 1, and m is an integer of zero or greater, which process comprises contacting sulfur dioxide, ethylene, optionally carbon monoxide, and optionally at least one ethylenically unsaturated hydrocarbon of at least 2 carbon atoms, in the presence of a catalyst obtained from (1) a compound of a Group VIII metal selected from palladium, cobalt and nickel, (2) a bidentate ligand of phosphorus, arsenic, or antimony, and (3) an anion of a non-hydrohalogenic acid having a pKa of less than 6.
摘要:
Aromatic oligomers, in particular arylene ketone and arylene sulfone oligomers, are prepared by reacting an appropriate monomer system in the presence of free Lewis acid and a complex between a Lewis acid, for example, aluminum trichloride, and a Lewis base, for example, N,N-dimethylformamide, and, optionally, a diluent, such as methylene chloride. The process is particularly advantageous for the preparation of substantially or all paralinked arylene ether ketone oligomers as the presence of the Lewis acid/Lewis base complex markedly reduces alkylation and ensures the substantial absence of ortho substitution. The monomer system can be, for example, a self-reacting monomer such as p-phenoxy-benzoyl chloride or a two-monomer system such as 1,4-diphenoxybenzene and terephthaloyl chloride.
摘要:
A process for producing an aromatic polyketone which comprises polymerizing an appropriate monomer or monomers by a Friedel-Crafts polymerization reaction using a Lewis acid catalyst. A controlling agent such as a Lewis base may be added to the reaction medium and/or the reaction is conducted under specified conditions to control the reaction. The reaction medium comprises, for example, aluminum trichloride as the Lewis acid, an organic Lewis base such as N,N-dimethylformamide or an inorganic Lewis base such as sodium or lithium chloride, and a diluent such as methylene chloride or dichloroethane. The amount of Lewis acid, the amount of Lewis base, the temperature of the reaction and the monomer to diluent molar ratio are varied depending on the monomer system to obtain melt-processable, high molecular weight, substantially linear polymers, for example poly(carbonyl-p-phenylene-oxy-p-phenylene), poly(carbonyl-p-phenylene-oxy-p-phenylene-oxy-p-phenylene), and the like. Copolymers containing up to 30% by weight of an aromatic sulfonyl halide comonomer can also advantageously be produced by this process.
摘要:
The preparation of poly(arylene ketones) and in particular all para-linked poly(arylene ether ketones) by Friedel-Crafts polymerization in the presence of a Lewis acid generally results in an intractible reaction product difficult to remove from the reaction vessel and difficult to purify. The addition of a liquefaction agent, such as a hydrogen halide and in particular hydrogen chloride, to the reaction mixture, results in a tractible gel or a liquid which can be readily handled. The hydrogen halide is preferably under pressure and a diluent may also be added along with the hydrogen halide.