Low melting point polyester fiber
The biggest advantage of low melting polyester fiber is to significantly reduce the environmental impact of the process of industrial chain processing, in particular, the elimination of the solvent-based adhesive, the direct spinning method can effectively prevent the degradation of the process of drying, can effectively inhibit Production of low molecular aldehydes.

For low melting point polyester fiber, although the domestic research earlier, but the process of industrialization is relatively slow, the main reasons are two: First, the traditional means to change the melting point of polyester is to add acid modified third monomer PIA (refined benzene Dicarboxylic acid), but will lead to increased manufacturing costs, market competitiveness decreased; Second, low melting point polyester drying is very difficult, seriously affecting the smooth spinning, but also may lead to polymer degradation, triggering a new safe use (Such as formaldehyde, acetaldehyde content increased).

With the industrialization of biochemical technology, the use of relatively low cost of alcohol modification method, can also make the melting point decreased, including the use of bio-based 1,4-butanediol (BDO) and 1,4-succinic acid (SA ), The melting point of the titanium catalyst is 114 ��, and the melting range is narrow, which is favorable for the drying of the slices. The melting point of the ternary copolymer PBST using BDO, SA and PTA can also be reduced to 140 �� Inhibition of low molecular weight aldehyde is significantly better than pure acid modified low melting point polyester fiber.
Biodegradable polyesters are used in the field of "disposable"
With the "disposable" market continues to develop, polyolefin fiber is difficult to bury the problem of degradation is increasingly prominent. Biodegradable Polyester 15 years ago, the first by the European and the United States to achieve industrialization, which is more famous is polylactic acid (PLA, represented by Nature Works) and poly adipic acid / butyl terephthalate (PBAT , Represented by BASF), its main application areas for the film, injection molding and fiber. It is difficult to recycle polyethylene, polyvinyl chloride, polypropylene and partially polystyrene, which are difficult to recite and decompose and produce harmful gases after the traditional "disposable" areas. Due to the high initial cost of raw materials and the degradation of polyester fibers Of the physical and chemical properties of PET fiber, the industrialization process is relatively slow.

Large-scale use of biodegradable polyester (PLA, PBAT, PBST, PBS) spinning and the formation of non-woven fabric technology key points include three aspects: First, to further reduce production costs; Second, the use of meltblown, spunbond Weaving cloth technology to make fiber fine denier, to further reduce the density is greater than the polyolefin caused by the loss of benefits (the same linear density of the degradation of polyester is more than 150% of polyolefin); third is to explore biodegradable polyester The surface treatment of fibers, including hydrophilic and water repellent treatment, to completely replace non-biodegradable polyolefin fibers.

Polyester elastic fibers
At present, the elasticity of garment fabrics mainly depends on polyurethane elastic fibers (such as Lycra ®), although the melt spinning spandex partially solved the previous dry and wet safety and environmental defects, but the synthetic spinning grade polyurethane is still more serious Costs (including "three wastes" emissions costs), textiles can not be recycled and other issues.

PTT and PET for the production of polyester fiber composite fiber to Invista (INVISTA) T400 the most prestigious, China's Sheng Hong, Haining new high has also produced similar parallel composite fiber. On the basis of PBT, the introduction of the third monomer polytetrahydrofuran (PTMEG) synthetic polyester elastomer, early as engineering plastics TPEE for high and low temperature environment of injection molding, foam materials, with the industrialization of PTMEG development, its Production costs have been significantly reduced, some universities and research units have been carried out TPEE for spinning research. Shanghai Petrochemical using titanium catalyst, synthetic TPEE and small spinning test equipment to explore, can significantly reduce the reaction temperature and reduce the reaction time, fiber elastic recovery rate of up to 80% of spandex.

Recycling technology of recycled polyester fiber
For a long time, the process of recycling polyester bottles of synthetic fiber is generally the process of mixing the PET bottles sorting cleaning, melt granulation and then sliced ​​dry, and finally through the screw extrusion spinning. Because of its melt-granulation process and the slice drying process is relatively difficult to control the original polyester, so the bottle-to-fiber products are often limited to the dyeing, fiber uniformity requirements are relatively low areas.

Germany Gneuss (Glenos) plastic technology company to develop the recovery of bottle-to-spinning technology is mainly composed of three parts: First, the use of a special extruder, provides a new method to remove small molecules. Second, the polymer rotating melt filter to ensure that the pressure and process stability, in the premise of fine filtration to shorten the residence time, and can be effective automatic cleaning. Third, the online viscometer real-time monitoring of stable polymer flow, according to the measured viscosity to adjust the vacuum, so that it is accurately maintained at the set value. All of which are conducive to ensuring uniform fiber, low breakage rate and good mechanical properties. China's China Textile Science Research Institute, Shanghai Juyou Chemical Co., Ltd. has also developed the key technology from the bottle to the polyester industry silk.