86results about How to "Improved melt stability" patented technology

Provided is a resin composition comprising 1-99% by weight of a modified ethylene-vinyl alcohol copolymer (C) having an ethylene content of 5-55 mol %, which contains a specific structural unit (I) in an amount of 0.3-40 mol % and can be obtained by reacting an ethylene-vinyl alcohol copolymer (A) with a monofunctional epoxy compound (B) having a molecular weight of not more than 500, and 1-99% by weight of a thermoplastic resin (T1) other than (C). Moreover, a multilayer structure in which the resin composition and a thermoplastic resin (T2) are laminated is also provided. Thus, a resin composition superior in barrier properties, transparency, stretchability, flexibility, flexing resistance and interlayer adhesiveness and various kinds of molded articles made thereof are provided.

It is an object of the present invention to provide a polylactic acid composition having excellent crystallinity, wet heat stability and melt stability. It is another object of the present invention to provide a molded article which is obtained from the polylactic acid composition and excellent in appearance and color. The present invention is a composition and molded article thereof which comprises a polylactic acid (component A), a carbodiimide compound (component B) and a phosphoric acid ester metal salt (component C).

An aromatic carbonate polymer composition having improved thermal stability consisting of an aromatic carbonate polymer such as a polycarbonate or polycarbonate/polyester blend and an impact modifier which is free of alkali materials which catalytically degrade a polycarbonate. Also an impact modifier which is preferably of a shell-core structure prepared by the emulsion polymerization process and has a pH of about 3 to about 8. A preferred emulsifier is an alkyl sulfonate having an alkyl group of C6-C18 carbons.

A glass composition satisfying the following conditions (A) to (L), the conditions are: (A) a content ratio of TeO₂ is in a range from 50 to 95 mol %; (B) a content ratio of B₂O₃ is in a range from 1 to 33 mol %; (C) a content ratio of ZnO is in a range from 1 to 37 mol %; (D) a content ratio of Bi₂O₃ is in a range from 1 to 18 mol %; (E) a content ratio of P₂O₅ is in a range from 0 to 15 mol %; (F) a content ratio of R₂O (where R represents at least one element selected from the group consisting of Li, Na, and K) is in a range from 0 to 13 mol %; (G) a content ratio of MO (where M represents at least one element selected from the group consisting of Mg, Ca, Sr, and Ba) is in a range from 0 to 13 mol %; (H) a content ratio of TiO₂ is in a range from 0 to 13 mol %; (I) a content ratio of Nb₂O₅ is in a range from 0 to 10 mol %; (J) a content ratio of Ta₂O₅ is in a range from 0 to 13 mol %; (K) a content ratio of L₂O₃ (where L represents at least one element selected from the group consisting of yttrium and lanthanoids) is in a range from 0 to 11 mol %; and (L) a content ratio of a total amount of P₂O₅, R₂O, MO, TiO₂, Nb₂O₅, Ta₂O₅, and L₂O₃ described in (E) to (K), respectively, is in a range from 0 to 15 mol %.

Disclosed is an EVOH resin composition which exhibits coloration resistance and thermal resistance even at high temperature, and which has excellent adhesiveness to a thermoplastic resin composition. Such EVOH resin composition can provide a multilayer structure having excellent appearance. The EVOH resin composition comprises (A) an EVOH resin, (B) an alkaline earth metal, (C) an alkali metal, and (D) a carboxylic acid having from 2 to 4 carbon atoms, wherein the contents of the components (B), (C) and (D) are adjusted to the specific range.

The invention provides an environment-friendly fireproof material for electrical equipment and a preparation method of the environment-friendly fireproof material, and belongs to the fields of fireproof materials and preparation technologies thereof. The environment-friendly fireproof material for the electrical equipment is characterized by being prepared from the following raw materials in parts by weight: 50 to 60 parts of modified epoxy resin, 30 to 40 parts of fluorocarbon resin, 60 to 90 parts of a fire retardant, 3 to 10 parts of expanded graphite, 3 to 10 parts of alumina silicate fiber and 2 to 8 parts of molecular sieves. The fireproof material provided by the invention is applied to fire protection of the electrical equipment, and is high in crack resistance, water resistance and weather resistance and good in expansion character; meanwhile, the heat release rate of a base material in a burning condition can be obviously reduced, and the quality loss is reduced; moreover, the fireproof material is small in smoke production quantity and good in environmental protection effect.

The invention discloses a method for preparing a high molecular weight vertical structure composite polylactic acid with melt stability characteristics. The method comprises the following steps: firstly, carrying out drying treatment on L-polylactide and dextral polylactic acid in vacuum, and then mixing an initiator which can be completely dissolved into absolute ethyl alcohol with a cross-linking agent, and then adding a mixture to a fusion mixer; melting and blending under the conditions that the temperature is 170-200 DEG C and the rotating speed is 20-120 rpm (revolutions per minute) for 2-15 minutes. The prepared high molecular weight vertical structure composite polylactic acid not only has excellent melt stability, but also has strong recrystallization ability, and can ensure that the vertical structure composite polylactic acid crystal with high purity and high content is reformed in a molten product, so as to provide excellent heat resistance and weather fastness to the product. The possibility is also provided for preparation of a PLA product with high performance by virtue of a melt processing technology. Meanwhile, the preparation method provided by the invention is simple in process, high in efficiency, and easy for realization of large-scale industrial production.

A thermoplastic composition comprising a resinous blend of (A) aromatic polycarbonate and (B) polyester, (C) nanoclay and (D) carboxylic acid is disclosed. The composition features improved melt stability and impact strength over corresponding compositions that contain no acid. The nanoclay is present in an amount of 0.1 to 30 percent relative to the weight of the resinous blend, and the acid is present in an amount of 1 to 20 percent relative to the weight of the nanoclay. The average thickness of the clay particles is about 1 to 100 nm, and their average lengths and average widths, independently one of the other are 50 to 700 nm.

The invention discloses a preparation method of nano particle grafted stereoblock polylactic acid. The method comprises the following steps that 1, under the anhydrous condition and protection of inert gas, nano particles with active groups on the surface are adopted as an initiator, metal carboxylate or metal alkoxide is adopted as a catalyst, levogyration or dextrorotation lactide is catalyzed to be subjected to ring opening polymerization at low temperature in an organic solvent, and nano particle grafted polylactic acid is obtained; 2, under the anhydrous condition and protection of inert gas, the obtained product is dissolved in an organic solvent, metal carboxylate or metal alkoxide is added for an activating reaction, and a high-activity polymer end-capped by specific functional groups is obtained; 3, the high-activity polymer is subjected to a ring-opening polymerization reaction with levogyration or dextrorotation lactide in an organic solvent, and nano particle grafted stereoblock copolymer is obtained. The invention further discloses the nano particle grafted stereoblock polylactic acid and application thereof. The preparation method is simple in process and easy to operate, and has industrial potential.

A styrene resin excellent in heat resistance, weatherability, melt stability, and suitability for recycling. It is a styrene copolymer obtained by living polymerization (M_w/M_n=1.6-4.0) which comprises isopropenylaromatic units (A) contained in an amount of 5 to 95 wt. % and vinylaromatic units, and has a glass transition temperature (T_g) which satisfies a specific relationship defined by the content of isopropenylaromatic units (A) in the copolymer.