Abstract: The invention relates to an epoxy resin composition and preparation thereof. The composition comprises the following blended components: 100 weight parts of epoxy resins; 30 to 120 weight parts of anhydride curing agents; 1 to 45 weight parts of powdery nitrile rubbers; no curing accelerator is included in the composition. The composition of the invention has both higher heat resistance and higher toughness, and is suitable for the fields which require high heat resistance, such as circuit board, electronics packaging, binder and electrical insulating coating etc.

Abstract: The present invention relates to a composite powder, preparation and use thereof. The composite powder according to the present invention is prepared by intimately mixing an irradiated or non-irradiated rubber latex with a slurry of inorganic particles in a ratio corresponding to that of rubber particles to inorganic particles in the composite powder according to the present invention, and then drying the resultant mixture. The composite powder according to the present invention comprises agglomerates composed of powdery rubber particles and inorganic particles, with inorganic particles being uniformly distributed either inside the agglomerats or both inside the agglomerates and on the surfaces thereof. The composite powder according to the present invention can be easily dispersed in plastic matrixes and thus can be compounded with plastics to produce toughened plastics and thermoplastic elastomers.

Abstract: The invention discloses a process for preparing high-performance propylene polymers, the process utilizing a high activity, highly stereoselective Ziegler-Natta catalyst and two or more stages of polymerization carried out under different hydrogen concentrations to prepare propylene polymers having broad molecular weight distribution, wherein non-unifomess of isotacticity of molecular chains of the final propylene polymers is improved by adjusting or controlling stereoselectivity of catalytic active sites under different hydrogen concentrations, namely, making the low molecular weight fraction of the polymers having a higher isotacticity and making the high molecular weight fraction of the polymers having a lower isotacticity, thereby overcoming the drawbacks of the propylene polymers having broad molecular weight distribution known in the art. The resulting final polymers have excellent combined properties, in particular, remarkably improved mechanical properties.

Abstract: The present invention provides a propylene polymer composition for producing a biaxially oriented film, comprising propylene random copolymer and propylene homopolymer; wherein the propylene random copolymer is a copolymer of propylene and ethylene, optionally comprising one or more alpha-olefins of C4-C10; the propylene polymer composition has an overall isotacticity index, as determined by nuclear magnetic resonance method, of greater than or equal to 96.5%, and an ethylene content of greater than 0.3 wt %; and wherein, the melt flow rate of the propylene random copolymer is lower than that of the propylene homopolymer. The biaxially oriented polypropylene film produced by the propylene polymer composition of the present invention exhibits excellent physical properties, and has, in the absence of any stiffening agent, relatively higher modulus and stiffness.

Abstract: The present invention provides a fully vulcanized thermoplastic elastomer comprising a rubber phase with a controllable particle size and a spheroidic shape, the preparation and use thereof. Fully vulcanized powdery rubber is blended with plastic by conventional method for blending rubbers, and thus obtaining a fully vulcanized thermoplastic elastomer, which comprises a rubber phase with a controllable particle size and a spheroidic shape, and which shows high tensile strength and high elongation at break, good appearance and good processibility.

Abstract: The present invention provides a propylene polymer composition for producing a biaxially oriented film, comprising propylene random copolymer and propylene homopolymer; wherein the propylene random copolymer is a copolymer of propylene and ethylene, optionally comprising one or more alpha-olefins of C4-C10; the propylene polymer composition has an overall isotacticity index, as determined by nuclear magnetic resonance method, of greater than or equal to 96.5%, and an ethylene content of greater than 0.3 wt %; and wherein, the melt flow rate of the propylene random copolymer is lower than that of the propylene homopolymer. The biaxially oriented polypropylene film produced by the propylene polymer composition of the present invention exhibits excellent physical properties, and has, in the absence of any stiffening agent, relatively higher modulus and stiffness.

Abstract: The present invention provides plastics with high toughness and the preparation thereof. The plastics with high toughness, which have the balance of stiffness and toughness, stable properties and good processability, are obtained by blending the rubber particles having an average particle size of 20 to 200 nm with the pseudoductile plastics, wherein the weight ratio of the rubber particles to the plastics is from 0.5:99.5 to 70:30. The present invention also provides plastics with both high stiffness and high toughness and the preparation thereof. The plastics with both high stiffness and high toughness, which have also an improved heat resistance and good processability, are prepared by blending the rubber particles having an average particle size of 20 to 500 nm and the crystalline plastics, wherein the amount of the rubber particles added in the plastics matrix is from 0.3 to 5 weight parts.

Abstract: The present invention relates to a composite powder, preparation and use thereof. The composite powder according to the present invention is prepared by intimately mixing an irradiated or non-irradiated rubber latex with a slurry of inorganic particles in a ratio corresponding to that of rubber particles to inorganic particles in the composite powder according to the present invention, and then drying the resultant mixture. The composite powder according to the present invention comprises agglomerates composed of powdery rubber particles and inorganic particles, with inorganic particles being uniformly distributed either inside the agglomerats or both inside the agglomerates and on the surfaces thereof. The composite powder according to the present invention can be easily dispersed in plastic matrixes and thus can be compounded with plastics to produce toughened plastics and thermoplastic elastomers.

Abstract: The present invention relates to a novel fully vulcanized powdery silicone rubber, preparation and use thereof. The fully vulcanized powdery silicone rubber is prepared from an latex of organosilicon polymer or copolymer with lower molecular weight via irradiation of high-energy rays. The gel content of the obtained fully vulcanized powdery silicone rubber is at least 60% by weight. The fully vulcanized powdery silicone rubber can be combined with various plastics and is very easy to be dispersed into plastic matrix, and can be used as toughening agent, processing aids or as additives for cosmetics, ink, paint and coatings.

Abstract: The present invention provides a toughened plastic and its preparation method, with said toughened plastic being obtained by rubber-plastic blending of brittle or less brittle plastics and a rubber mixture. Said rubber mixture consists of powdery rubbers having a cross-linked structure and an average particle size of not more than 0.50 &mgr;m, and at least one selected from the group consisting of unvulcanized rubbers and thermoplastic elastomers. The morphology and the particle size distribution of the rubber phase contained in said toughened plastic can be controlled by changing the particle size of the powdery rubbers having a cross-linking structure and choosing proper unvulcanized rubbers or thermoplastic elastomers. The toughened plastic, according to the present invention has good toughness and processability while keeping better strength and stiffness.

Abstract: The present invention relates to a novel fully vulcanized powdery silicone rubber, preparation and use thereof. The fully vulcanized powdery silicone rubber is prepared from an latex of organosilicon polymer or copolymer with lower molecular weight via irradiation of high-energy rays. The gel content of the obtained fully vulcanized powdery silicone rubber is at least 60% by weight. The fully vulcanized powdery silicone rubber can be combined with various plastics and is very easy to be dispersed into plastic matrix, and can be used as toughening agent, processing aids or as additives for cosmetics, ink, paint and coatings.

Abstract: The present invention provides toughened thermosetting resins and preparation of the same. The toughened thermosetting resins according to the present invention comprise thermosetting resins and rubber particles having an average particle size in the range of 20 to 500 nm. The toughened resins are obtained by mixing a fully vulcanized powdery rubber having an average particle size in the range of 20 to 500 nm with thermosetting resin prepolymers and then curing them. The toughened thermosetting resins according to the present invention comprise rubber phases having a small, uniform and stable particle size, which results in a very significant toughening effect, especially when crazes rapidly grow (as in a standard Izod impact test).

Abstract: The present invention provides a fully vulcanized thermoplastic elastomer comprising a rubber phase with a controllable particle size and a spheroidic shape, the preparation and use thereof. Fully vulcanized powdery rubber is blended with plastic by conventional method for blending rubbers, and thus obtaining a fully vulcanized thermoplastic elastomer, which comprises a rubber phase with a controllable particle size and a spheroidic shape, and which shows high tensile strength and high elongation at break, good appearance and good processibility.

Abstract: The present invention provides plastics with high toughness and the preparation thereof. The plastics with high toughness, which have the balance of stiffness and toughness, stable properties and good processability, are obtained by blending the rubber particles having an average particle size of 20 to 200 nm with the pseudoductile plastics, wherein the weight ratio of the rubber particles to the plastics is from 0.5:99.5 to 70:30. The present invention also provides plastics with both high stiffness and high toughness and the preparation thereof. The plastics with both high stiffness and high toughness, which have also an improved heat resistance and good processability, are prepared by blending the rubber particles having an average particle size of 20 to 500 nm and the crystalline plastics, wherein the amount of the rubber particles added in the plastics matrix is from 0.3 to 5 weight parts.

Abstract: The present invention provides a fully vulcanized powdery rubber having a particle size of from 20 to 2000 nm, its preparation and use. The vulcanized powdery rubber is obtained by irradiating a rubber latex having a particle size of from 20 to 2000 nm with a high-energy irradiation. The vulcanized powdery rubber is very easily to be dispersed into various plastics, and thus can be mixed with various plastics to prepare toughened plastics and fully valcanized thermoplastic elastomers.