Abstract: The invention discloses a flame-retardant semi-aromatic polyamide derived from the following monomers: a diacid monomer A: where A1 is terephthalic acid or terephthalic acid and other diacid, terephthalic acid accounts for 50 to 100 mol % of A1, and A2 is [(6-oxido-6H-dibenzo-(c,e)(1,2)-oxaphosphorin-6-ketone)-methyl]-butanedioic acid, A1+A2=100 mol %, A1=90 to 99 mol %, A2=1 to 10 mol %; and diamine monomer B: one or more of diamine monomers containing 4 to 36 carbon atoms. In the present invention, by an in situ polymerization, a specific flame-retardant monomer [(6-oxido-6H-dibenzo-(c,e)(1,2)-oxaphosphorin-6-ketone)-methyl]-butanedioic acid is copolymerized in a semi-aromatic polyamide chain segment, excellent mechanical properties and low water absorption can be obtained.

Abstract: Disclosed in the present invention is a semiaromatic polyester, a preparation method and application thereof. Having a specific segment length and carboxyl group content, the semiaromatic polyester provides a balance of degradation rate and mechanical properties, compared with known semiaromatic polyesters. The 30-day weight retention of the semiaromatic polyester obtained in the present invention may be contained to from 45 to 70%.

Abstract: The present invention discloses a biodegradable polyester composition, wherein the biodegradable polyester composition comprises the following components in parts by weight: i) 58 to 80 parts by weight of an aliphatic-aromatic copolyester; ii) 20 to 32 parts by weight of starch; and iii) 0 to 10 parts by weight of a processing agent. The present invention unexpectedly found by research that by using an aliphatic-aromatic copolyester in which an amount of aromatic carboxylic acid accounts for a total amount of diacid is 44 mol % to 48 mol % as a matrix resin, where the aliphatic-aromatic copolyester has a crystallization peak width D of 5° C. to 16° C.

Abstract: The present invention provides a polyformaldehyde composite material, in parts by weight, including the following components: 70 to 95 parts of a polyformaldehyde; 5 to 20 parts of a SEBS; wherein, the SEBS is acid modified or amine modified. Due to modification by acid or amine, and presence of a polystyrene segment, a compatibility of the SEBS with the polyformaldehyde reduces because of a steric hindrance effect, which reduces an ability of a POM molecular chain to arrange regularly. When injection molded into a product or template, an incompatibility of the material itself will form a micro-rough effect on a surface of the material. When an incident light reaches the micro-rough surface, a reflection direction of the light will change and thus a diffuse reflection occurs, and a low-gloss material is obtained.

Abstract: The present invention discloses a measuring method for a semiconductor gas sensor based on alternating-current impedance. The method includes the steps: connecting the semiconductor gas sensor to a capacitor in parallel, connecting an alternating-current impedance measuring device to the semiconductor gas sensor and the capacitor, combining measuring parameters under measuring frequencies within a first preset range and parallel capacitance values within a second preset range, and measuring a gas with a known concentration according to each of nine features under each combination; traversing all parameter combinations and all the nine features to obtain a plurality of feature values corresponding to the same gas concentration under each feature; and selecting measuring frequencies within a third range, parallel capacitance values within a fourth range and a certain or several of the corresponding features as measuring parameters finally selected for measuring an unknown gas concentration.

Abstract: The invention discloses a method for measuring a semiconductor gas sensor based on virtual alternating current impedance. The method comprises: combining measurement parameters of virtual measurement frequencies in a first predetermined range and virtual parallel capacitance values in a second predetermined range, and measuring gas with known concentrations at each characteristic quantity among nine characteristic quantities in the case of each combination; obtaining multiple characteristic values corresponding to the same gas concentration at each characteristic quantity after traversing all parameter combinations and all nine characteristic quantities; and selecting virtual measurement frequencies in a third range, virtual parallel capacitance values in a fourth range and one or several corresponding characteristic quantities as the finally selected measurement parameters for measuring the unknown gas concentration.

Abstract: The present invention provides a polypropylene-polyphenylene ether-polystyrene ternary alloy, including the following components in parts by weight: 100 parts of a polypropylene and a polyphenylene ether and a polystyrene, wherein the polypropylene accounts for 10% to 60%, the polyphenylene ether accounts for 10% to 60%, and the polystyrene accounts for 5% to 30%; 5 parts to 25 parts of a compatibilizer; and 10 parts to 60 parts of a polyphosphate compound. The polypropylene-polyphenylene ether-polystyrene ternary alloy of the present invention has an advantage of a less smoke release amount during melt.

Abstract: The present application is related to a polycarbonate composition, including 100 parts of a polycarbonate in parts by weight; wherein based on a total weight percentage of the polycarbonate, the polycarbonate consists of 10% to 40% of a first polycarbonate with a weight average molecular weight of 18,000 to 25,000, 20% to 60% of a second polycarbonate with a weight average molecular weight of 27,000 to 35,000, and 20% to 60% of a third polycarbonate with a degree of branching of 2 to 7 and a weight average molecular weight of 25,000 to 30,000. The polycarbonate composition has the advantages of high transparency, good extrusion melt uniformity, etc.

Abstract: The present invention relates to a flame-retardant nylon composite and use thereof, including components: 55 parts to 80 parts of a nylon resin; 1 part to 30 parts of a red phosphorus; and 0.01 part to 2 parts of a phenolic substance. According to the present invention, by adding a small amount of the phenolic substance to the red phosphorus flame-retardant nylon composite, phosphorus precipitation can be effectively inhibited, and a phosphine precipitation amount can be reduced to 30 ppm or less, while good electrical performances can be maintained, which is applicable in fields of connectors, contactors, etc. in electronic appliances.

Abstract: The present invention discloses a polycarbonate alloy, including the following components in parts by weight: 80 parts of a polycarbonate; and 5 parts to 30 parts of an ethylene copolymer.

Abstract: The present invention discloses a high weld line strength polypropylene/polycarbonate alloy, including the following components in parts by weight: 5 parts to 40 parts of a polypropylene; 40 parts to 85 parts of a polycarbonate; and 1 part to 15 parts of an ethylene copolymer compatibilizer. The high weld line strength polypropylene/polycarbonate alloy has high weld line strength, a good melt index and an excellent chemical resistance.

Abstract: The present invention provides a polycarbonate alloy including the following components in parts by weight: 50 parts to 80 parts of a polycarbonate; 1 part to 50 parts of a crystalline polyester; 0.01 part to 4 parts of a maleic anhydride polymer; and 0.01 part to 4 parts of a metal phosphate. The polycarbonate alloy of the present invention has advantages of good alloy stability, and a continuous and uniform distribution of the crystalline polyester in the alloy.

Abstract: The present invention discloses a high weld line strength polyethylene/polycarbonate alloy, including the following components in parts by weight: 5 parts to 40 parts of a polyethylene; 40 parts to 85 parts of a polycarbonate; and 1 part to 15 parts of an ethylene copolymer compatibilizer. The high weld line strength polyethylene/polycarbonate alloy has the advantages of high weld line strength, a good melt index and a good thermal aging resistance.

Abstract: The present invention discloses a polylactic acid composite and use thereof. The polylactic acid composite includes the following components: i) 50-85 parts by weight of polylactic acid; ii) 8 to 35 parts by weight of an inorganic filler; and iii) 0 to 8 parts by weight of a plasticizer; wherein the polylactic acid composite has an end carboxyl content of 12 to 51 molKOH/t. The present invention unexpectedly discovered through research that, by controlling an end carboxyl content of the polylactic acid composite within a range of 12 to 51 molKOH/t, the polylactic acid composite, under a condition of 60° C. and 60% humidity, with a test time of 30 days, has a ratio of a mass melt index MFIt=30 to an initial mass melt index MFIt=0 satisfying 3.5<?=MFIt=30/MFIt=0<5.1, which indicates that under the test conditions, the product has slow aging degradation, and the polylactic acid composite has a biodegradation rate greater than 90% after 12 weeks in the case where a thickness is 2.

Abstract: Disclosed is a flame-retardant HIPS material and a preparation method thereof, comprising the following components: 79 parts to 91 parts of a HIPS resin; 2 parts to 8 parts of a brominated flame retardant; and 3 parts to 7 parts of an auxiliary flame retardant; wherein the auxiliary flame retardant is a 1,3,5-triazine compound. In the present invention, a synergistic compounding of the brominated flame retardant and the auxiliary flame retardant effectively reduces an amount of the brominated flame retardant, and a stable UL 94 (1.5 mm) V-2 flame-retardant class can be achieved. Compared with the existing brominated flame-retardant HIPS, the present invention has a low halogen content, low gas, high cost performance ratio, relatively good thermal stability, and relatively light corrosiveness to the mold, and can be widely applied in the field of thin-walled parts, such as office equipment, video multimedia, household appliances and the like.

Abstract: The present invention relates to a biodegradable polyester and use thereof, including components: A) acid components containing following repeating units: 50 to 58 mol % of terephthalic acid A1; 30 to 40 mol % of sebacic acid A2; and 2 to 20 mol % of an aliphatic dibasic acid A3 with a carbon chain length of 6 or less; B) butanediol. In the present invention, in the case of a high content of the terephthalic acid, the biodegradable polyester prepared by introducing an aliphatic dibasic acid unit having a carbon chain length of 6 or less can satisfy the degradation performance and rigidity and improve the tenacity of the material simultaneously.

Abstract: A biodegradable polyester and use thereof includes components: A) acid components containing following repeating units: 40 to 48 mol % of terephthalic acid A1; 38.5 to 50 mol % of sebacic acid A2; and 2 to 20 mol % of an aliphatic dibasic acid A3 with a carbon chain length of 6 or less; B) butanediol. In the case of low content of the terephthalic acid unit, by introducing the aliphatic dibasic acid unit with the carbon chain length of 6 or less, mechanical properties of the material can be significantly improved, and the mechanical property retention is better especially when stored in a humid environment.

Abstract: Disclosed is a low-odor combustion-delaying polyolefin composition, which includes the following components by weight percentage: 56% to 99.7% of polyolefin; 0.3% to 2% of an ethoxyamide polymer; 0% to 2% of a delay combustion synergist; and 0% to 40% of a filler. Disclosed is also a use of the ethoxyamide polymer as a delay combustion agent in the polyolefin composition.

Abstract: A biodegradable polyester and use thereof includes components: A) acid components containing following repeating units: 40 to 48 mol % of terephthalic acid A1; 38.5 to 50 mol % of sebacic acid A2; and 2 to 20 mol % of an aliphatic dibasic acid A3 with a carbon chain length of 6 or less; B) butanediol. In the case of low content of the terephthalic acid unit, by introducing the aliphatic dibasic acid unit with the carbon chain length of 6 or less, mechanical properties of the material can be significantly improved, and the mechanical property retention is better especially when stored in a humid environment.

Abstract: The present invention discloses a biodegradable polyester composition, wherein the biodegradable polyester composition comprises the following components in parts by weight: i) 58 to 80 parts by weight of an aliphatic-aromatic copolyester; ii) 20 to 32 parts by weight of starch; and iii) 0 to 10 parts by weight of a processing agent. The present invention unexpectedly found by research that by using an aliphatic-aromatic copolyester in which an amount of aromatic carboxylic acid accounts for a total amount of diacid is 44 mol % to 48 mol % as a matrix resin, where the aliphatic-aromatic copolyester has a crystallization peak width D of 5° C. to 16° C.