Abstract: A method for improving the quality of a polyester industrial yarn is provided. First, in the cooling process of preparing a polyester industrial yarn prepared by polyester spinning, the longitudinal height is kept unchanged, and the cross-sectional area of the slow cooling chamber is enlarged. The chamber maintains the surface temperature of the spinneret by means of heat preservation, and then uses an oil agent containing 67.30-85.58 wt % crown ether in the oiling process of polyester industrial yarn prepared by polyester spinning. Enlarging the cross-sectional area of the slow-cooling chamber refers to the cross section of the slow cooling chamber is changed from a circular shape to a rectangular shape while keeping the spinneret connected to the slow cooling chamber unchanged. The cleaning cycle of the spinneret is prolonged by 35-45%, the full package rate of polyester industrial yarn is larger than 99%.

Abstract: A lightweight heat-preserving fiber and a preparation method thereof are provided, wherein the fiber is prepared by measuring, composite spinneret's extruding, cooling, oiling, drawing, heat setting and winding a polyester melt. The composite spinneret has a hollow spinning hole and a circular spinning hole. The ratio of the micropore length of hollow spinning hole to circular spinning hole equals to the ratio of the equivalent diameter of hollow spinning hole to circular spinning hole multiplies the coefficient K, and the equivalent diameter is the ratio of the cross-sectional area to the circumference of the cross-section, the coefficient K ranges from 0.97 to 1.03. The oil agent contains a crown ether, and the content of the crown ether ranges from 67.30 to 85.58 wt %. The thermal conductivity of a knitted fabric having a basis weight of 100 g/m2 prepared by lightweight heat-preserving fiber is no larger than 0.150 W/m·K.

Abstract: A bi-profiled fiber and preparing method thereof are provided. The bi-profiled fiber is manufactured through the steps of spinning melt metering, extruding via the composite spinneret, cooling, oiling, drawing, heat setting and winding, finally containing both double-cross monofilaments and circular monofilaments simultaneously. The bi-profiled fiber is made of the modified polyester, and the modified polyester is dispersed by matte agent and is composed of terephthalic acid segments, ethylene glycol segments and branched diol segments, and the branched diol segment has a structural formula of where R1 and R2 are separately selected from the linear alkylene with 1-3 carbon atoms, R3 from the alkyl with 1-5 carbon atoms, and R4 from the alkyl with 2-5 carbon atoms. The matte agents is a mixture of amorphous titanium dioxide and amorphous silicon dioxide, or a mixture of calcium carbonate and amorphous silicon dioxide.

Abstract: A low-shrinkage polyester industrial yarn and a preparation method thereof are provided. The preparation method includes the following steps: subjecting the modified polyester to polycondensation, melting, measuring, extruding, cooling, oiling, stretching, heat setting and winding, wherein the content of the crown ether in the oil agent is 67.30-85.58 wt %. The material of the prepared low shrinkage polyester industrial yarn is a modified polyester, the molecular chain of the modified polyester includes a terephthalic acid segment, an ethylene glycol segment, and a branched diol segment, and the structural formula of the branched diol is as follows: Wherein R1 and R2 are each independently selected from a linear alkylene group having 1-3 carbon atoms, R3 is selected from an alkyl group having 1-5 carbon atoms, and R4 is selected from an alkyl group consisting of 2-5 carbon atoms.

Abstract: A high uniformity coloured polyester industrial yarn and preparation method. The raw material of the high-uniformity coloured polyester industrial yarn is the modified polyester composed of terephthalic acid segment, an ethylene glycol segment and a branched diol. The high-uniformity coloured polyester industrial yarn is prepared by esterification reaction of terephthalic acid with a branched diol using concentrated sulfuric acid as catalyst to obtain terephthalic acid glycol ester. Terephthalic acid and ethylene glycol are formulated to carry out esterification reaction to obtain ethylene terephthalate. Finally, stir and mix the two materials and carry out the polycondensation reaction in the low vacuum stage and the high vacuum stage under the action of the catalyst and the stabilizer to obtain modified polyester. Measure the modified polyester and add black masterbatch.

Abstract: A one-step spun composite DTY and preparation method thereof are provided. The bi-profiled fiber is manufactured with two types of modified polyester of different viscosities through the steps of melting, melt metering, composite extruding, cooling, oiling, drawing, heat setting and winding. Wherein those two modified polyesters have a molecular structure including terephthalic acid segments, ethylene glycol segments and branched diol segments, and the branched diol has a structural formula of here R1 and R2 are separately selected from the linear alkylene with 1-3 carbon atoms, R3 from the alkyl with 1-5 carbon atoms, and R4 from the alkyl with 2-5 carbon atoms. The obtained one-step spun composite DTY has an elastic shrinkage rate of no less than 35%. The method presented in this invention is involved in a simple and reasonable technological process for wide application range.

Abstract: A porous ultra-soft ultra-fine denier polyester fiber and preparation method. The modified polyester is spun with a porous spinneret to produce the porous ultra-soft ultra-fine denier polyester fiber, and the spinneret holes on the porous spinneret are arranged in an elliptical arrangement. The porous ultra-soft ultra-fine denier polyester fiber is obtained by metering, extruding, cooling, oiling and high-speed winding the modified polyester chips. The preparation method of modified polyester is as follows: terephthalic acid reacts with ethylene glycol to produce ethylene terephthalate. The modified polyester is obtained by the reaction of terephthalic acid with branched diol. The fiber of the invention has good properties and the deviation rate of fiber density. The deviation rate of fiber density is ?0.5%, the CV value of breaking strength is ?4.0%, the CV value of elongation at break is ?8.0%, the CV value of yarn unevenness is ?2.0%.

Abstract: A different shrinkage composite yarn and preparation method. The modified polyester is spun with a porous spinneret to produce a different shrinkage composite yarn, and the spinneret holes on the porous spinneret are arranged in an elliptical arrangement. The different shrinkage composite yarn is obtained by winding modified polyester POY yarn and FDY yarn, network recombining, and coiling them. The preparation method of modified polyester is as follows: terephthalic acid reacts with ethylene glycol to produce ethylene terephthalate. The modified polyester is obtained by the reaction of terephthalic acid with branched diol. The fiber of the invention has good properties and the deviation rate of fiber density. The CV value of breaking strength is ?4.0%, the CV value of elongation at break is ?8.0%, the CV value of coefficient of variation of coiling shrinkage is ?8.0%.

Abstract: A method for preparing the modified polyester. The modified polyester segments include terephthalic acid segment, ethylene glycol diol segment and branched diol segment, in which the branched diol segment refers to a diol segment in which a branch is located on a non-terminal carbon in the glycol segment and the branch is a linear carbon chain having 5 to 10 carbon atoms. The method includes preparing terephthalic acid glycol ester through the esterification of terephthalic acid and branched diol using the concentrated sulfuric acid as the catalyst. Then get ethylene terephthalate through the esterification of terephthalic acid and ethylene glycol. After stirring and mixing the two, the modified polyester can be obtained through polycondensation reaction of a low vacuum stage and a high vacuum stage using the catalyst and stabilizer.

Abstract: A low chromatic aberration polyester different-shrinkage composite yarn is made of polyester POY yarn and polyester FDY composite yarn. The polyester POY yarn and polyester FDY yarn is obtained by spinning the polyester solution, the rupture strength of the low color polyester different-shrinkage composite yarn is ?1.9 cN/dtex, the elongation at break is 30.0±5.0%, the crimp shrinkage is 2.50±3.0%, the network degree is 20±5/m, the color difference ?E is less than 0.200. In the invention, the magnesium ethylene glycol is relatively mild, the thermal degradation coefficient is small, the oligomers in the polymerization process is reduced, and the oligomers in the dissolution process are further reduced, so that the appearance of stains and streaks reduces during the dyeing and post-processing heat setting of the polyester fiber, which ensures the fiber's leveling and rubbing fastness.

Abstract: A polyester obtained by the esterification of terephthalic acid and ethylene glycol and the polycondensation catalysed by a mixture of magnesium ethylene glycol and antimony ethylene glycol followed by granulation. In the polyester sections, the carboxyl end group is less than 15 mol/t, the mass percentage of oligomer is lower than 0.5%, and weight percentage of diethylene glycol is lower than 0.5%.

Abstract: A porous ultra-soft ultra-fine denier polyester fiber and preparation method. The modified polyester is spun with a porous spinneret to produce the porous ultra-soft ultra-fine denier polyester fiber, and the spinneret holes on the porous spinneret are arranged in an elliptical arrangement. The porous ultra-soft ultra-fine denier polyester fiber is obtained by metering, extruding, cooling, oiling and high-speed winding the modified polyester chips. The preparation method of modified polyester is as follows: terephthalic acid reacts with ethylene glycol to produce ethylene terephthalate. The modified polyester is obtained by the reaction of terephthalic acid with branched diol. The fiber of the invention has good properties and the deviation rate of fiber density. The deviation rate of fiber density is ?0.5%, the CV value of breaking strength is ?4.0%, the CV value of elongation at break is ?8.0%, the CV value of yarn unevenness is ?2.0%.

Abstract: A method for preparing the modified polyester. The modified polyester segments include terephthalic acid segment, ethylene glycol diol segment and branched diol segment, in which the branched diol segment refers to a diol segment in which a branch is located on a non-terminal carbon in the glycol segment and the branch is a linear carbon chain having 5 to 10 carbon atoms. The method includes preparing terephthalic acid glycol ester through the esterification of terephthalic acid and branched diol using the concentrated sulfuric acid as the catalyst. Then get ethylene terephthalate through the esterification of terephthalic acid and ethylene glycol. After stirring and mixing the two, the modified polyester can be obtained through polycondensation reaction of a low vacuum stage and a high vacuum stage using the catalyst and stabilizer.

Abstract: A different shrinkage composite yarn and preparation method. The modified polyester is spun with a porous spinneret to produce a different shrinkage composite yarn, and the spinneret holes on the porous spinneret are arranged in an elliptical arrangement. The different shrinkage composite yarn is obtained by winding modified polyester POY yarn and FDY yarn, network recombining, and coiling them. The preparation method of modified polyester is as follows: terephthalic acid reacts with ethylene glycol to produce ethylene terephthalate. The modified polyester is obtained by the reaction of terephthalic acid with branched diol. The fiber of the invention has good properties and the deviation rate of fiber density. The CV value of breaking strength is ?4.0%, the CV value of elongation at break is ?8.0%, the CV value of coefficient of variation of coiling shrinkage is ?8.0%.

Abstract: The present invention discloses an ultra-low shrinkage polyester industrial yarn and its preparation method. The ultra-low shrinkage polyester industrial yarn is prepared by subjecting a polyester to dissolution, washing and solid state polycondensation followed by spinning. The ultra-low shrinkage polyester industrial yarn has a dry heat shrinkage rate of 1.8±0.25% under test conditions of 177° C.×10 min×0.05 cN/dtex. The polycondensation catalyst consists of magnesium ethylene glycol and antimony ethylene glycol, has a small thermal degradation coefficient. The present invention reduces oligomers during polymerization, reduces thermal degradation during processing, and as a result the invention greatly reduces impurities and nucleating agent in the polyester, leading to an increase in the probability of homogeneous nucleation based on the reduction of heterogeneous nucleation.

Abstract: A low chromatic aberration polyester different-shrinkage composite yarn is made of polyester POY yarn and polyester FDY composite yarn. The polyester POY yarn and polyester FDY yarn is obtained by spinning the polyester solution, the rupture strength of the low color polyester different-shrinkage composite yarn is ?1.9 cN/dtex, the elongation at break is 30.0±5.0%, the crimp shrinkage is 2.50±3.0%, the network degree is 20±5/m, the color difference ?E is less than 0.200. In the invention, the magnesium ethylene glycol is relatively mild, the thermal degradation coefficient is small, the oligomers in the polymerization process is reduced, and the oligomers in the dissolution process are further reduced, so that the appearance of stains and streaks reduces during the dyeing and post-processing heat setting of the polyester fiber, which ensures the fiber's leveling and rubbing fastness.

Abstract: A polyester obtained by the esterification of terephthalic acid and ethylene glycol and the polycondensation catalysed by a mixture of magnesium ethylene glycol and antimony ethylene glycol followed by granulation. In the polyester sections, the carboxyl end group is less than 15 mol/t, the mass percentage of oligomer is lower than 0.5%, and weight percentage of diethylene glycol is lower than 0.5%.

Abstract: The present invention discloses an ultra-low shrinkage polyester industrial yarn and its preparation method. The ultra-low shrinkage polyester industrial yarn is prepared by subjecting a polyester to dissolution, washing and solid state polycondensation followed by spinning. The ultra-low shrinkage polyester industrial yarn has a dry heat shrinkage rate of 1.8±0.25% under test conditions of 177° C.×10 min×0.05 cN/dtex. The polycondensation catalyst consists of magnesium ethylene glycol and antimony ethylene glycol, has a small thermal degradation coefficient. The present invention reduces oligomers during polymerization, reduces thermal degradation during processing, and as a result the invention greatly reduces impurities and nucleating agent in the polyester, leading to an increase in the probability of homogeneous nucleation based on the reduction of heterogeneous nucleation.

Abstract: A flame-retardant polyester fiber obtained by spinning flame-retardant polyester and irradiating with ultraviolet light and having a limiting oxygen index value of greater than 30. Flame retardant 2-carboxyethylphenylphosphinic acid to improve the flame retardant properties of polyester, the use of polyester containing unsaturated double bond in UV irradiation, the double bond opens to form a crosslinking point, the formation of a certain amount of the network structure improves the heat-resistant temperature of the poly-fiber and improves the anti-dripping performance of the polyester fiber.

Abstract: A high-modulus low-shrinkage polyester industrial yarn obtained by subjecting a polyester to dissolution, washing and solid state polycondensation followed by spinning. The high-modulus low-shrinkage polyester industrial yarn has a dry heat shrinkage rate of 2.0±0.25% under test conditions of 177° C.×10 min×0.05 cN/dtex. The average value of the crystal volume VC of the high-modulus low-shrinkage polyester industrial yarn is larger than 230 mm3. The high-modulus low-shrinkage polyester industrial yarn has a fiber modulus of ?100 cN/dtex. The polycondensation catalyst consists of magnesium ethylene glycol and antimony ethylene glycol, which has a small thermal degradation coefficient.