Blending Modification Of Polylactide Fiber For Better Softness

Polylactide(PLA),as biodegradable polyester produced from renewable resources,has became currently the most widely usecl biodegradable materials due to its good biodegradability,biocompatibility and excellent physical properties and other aclvantages.However,compared with the conventional fiber material,polylactic acid fiber 1s of poor softness property and hardness.With the change of need for more comfortable,softness of the fabric has become one of the most important assessment indicators of Textile fabrics producer.With consumers’ increasing demand for high quality fabrics and their feeling of "the softer,the better",improving the softness of PLA becomes more important for its large-scale commercial applications in the textile and non-woven industry.Here we will use polyethylene glycol(PEG)as modified material to produced a variety of blend fibers via melt-spinning and drawing steps.And reseach the structure and properties of the blend fibers.Then blend fibers knitted and characterized its texture.Specific studies and research results are as follows:Fristly,We prepared the PLA/PEG and PLA/PEG/MDI blend fibers by melt-spinning,Discussed spinnability and spinning process.investigated stability,spinnability,hydrophilic properties and softness of blend fiber via then11al performance tests,SEM scanning test monotilament strength,hydrophilicity test,KES and so on.The results showed the best processing conclitions as follows:PLA/PEG blends is poor of-high temperature stability,Addition of plasticizers can improve high temperature stability fiber ancl the compatibility,mainly caused by Chain reaction with MDI.Mechanical test results with increasing PEG content,the elongation at break gradually increased.the modulus and strength were reduced Fiber brittleness has been improved,the addition of compatibilizer MDI blend fibers still vvas of toughness;After blending,PLA fibers turned a hydrophilic fiber into hvdrophobic fibers;Blend fiber bending stiffness was lower than that of pure PLA fibers,deformation capacity increased,bLit blended fabric surface friction increasingly large surface irregularities,after adding compatibilizer slightly reduced surface friction small.Then,to improve compatibility of the plasticizer and PLA matrix,We prepared PEG and lactide copolymer,obtained copolymer which embedded short-chain of PEG.We investigated the structure of the copolymer via infrared NMR,Gel,permeation chromatography.PEG-PLA copolymer is a block copolymer.Finally,we prepared the PLA/PLA-PEG-PLA,blend fibers by melt blending with the plasticizer obtained by copolynerizing.compared with MDI plasticizer,PLA/PLA-PEG-PLA blend had the best high temperature stability;mechanical properties derived PLA/PLA-PEG-PLA blend fiber strength and modulus decreased,elongation at break decreased dramatically increased,fiber exhibits good toughness;PLA/PLA-PEG-PLA blend fibers still hydrophilic fibers,and the hydrophilicity is further improved;KES test results showed,the bending stiffness of the PLA/PLA-PEG-PLA blend fiber decreased,the fibers lore easily deformed under the action of an external force、the fiber blend flexibility has been greatly improved,the surface flatness and surface roughness of blend fibers decreased to improved PLA fiber softness.In summary,the modified PLA fiber was of better flexibility preparation and sinple production process is,has a certain significance for industrial mass production.