Study On Preparation And Properties Of PA56/PET Composite Fibers

The way that using simple technological process for raw material to obtain new materials has been obtained the researchers attention.Polyethylene terephthalate fiber is widely used as the largest production varieties of synthetic fiber in China,but due to its fiber structure,poorer hygroscopicity,poorer permeability,poorer dyeing and poorer tactility,the further development is limited.Bio-based nylon 56,a new type of environmental friendly material,is polymerizated by the biological diamine and petroleum adipic acid.It has good hydrophilicity,elasticity,low temperature dyeing performance,flame retardant.Bio-based content reached 41%.In recent years,The biological method to product 1,5-pentamethylenediamine developed by the Shanghai KaiSai Biotechnology Co,Ltd has been a great success,Production efficiency has been improved.The cost significantly has been lower.Thus the industrial application of nylon 56 become possible.There are so many scholars studying the blending of PET/PA6 or PET/PA66,while few study on PET/PA56 blend or composite.This paper has studied the crystalline and spinnability of PET/PA56 to obtain a new material which has excellent comprehensive.The cost of this new material is much lower,development time is shorter.The study on the compatibility,crystallization properties and thermal stability,mechanical properties of filam is indispensable,which can be tested by the method of DSC,SEM,XRD and so on.The main direction and experimental conclusion of the paper are as follows:(1)Compatibility study: DSC test identifying the two kinds of polymer belongs to crystal respectively;SEM test that two phase has obvious boundaries.(2)Compatibility study: the thermal properties of blends was tested by DSC,and the results showed that the two polymers in the blend are separately crystallized;SEM test result showed that the two phases have obvious boundaries.Crystallization study: DSC test found that with the weight ratio of PA56 increase,PET super-cooling is reduced,the crystallization rate increases.Wide Angle X-ray diffraction(WXRD)test the crystallinity of blend,which found that the blend crystallinity decreases with weight ratio of PA56 increasing..(3)Thermal study: TGA shows the initial degradation temperature of blend is lower than pure PET.(4)Filament structure study: the filament orientation degree test by the sound velocity method,and the results have shown that PA56 lead filament orientation degree to decline;under the same draft,as time goes away,filament orientation is decreased;as PA56 added to PET,the elongation at break increased,the initial modulus decrease,moisture regain increase,and the boiling water shrinkage decrease and then increase.(5)The breaking strength of composite filament is between 2.5 cN/dtex and 2.8 c N/dtex;moisture is between PA56 and pure PET.Based on the study of the compatibility,crystallinity and distribution of the blends,the spinnability and filament performance were studied.The orientation,mechanical properties,elastic recovery rate and resurgence of filament were studied.In the aspect of composite spinning,the spinning process and the orientation degree of composite yarn,mechanical property,elastic recovery rate and moisture regain were studied.