Study On The Properties And Spinnability Of PHBV/PLA Biomass Fiber

In the context of environment-friendly,low-carbon economy and sustainable development,the biomass textiles are the focus of research.At present,the development of biomass fiber and textiles in China is still in infancy.Therefore,the blended fiber of polylactic acid fiber(PLA)and poly(3-hydroxybutyrate)-co-3-hydroxyvalerate(PHBV)fiber(PHBV/PLA)are the researched material of the study.At first,the microstructure,mechanical properties,moisture regain,friction,curling and antibacterial properties of the fibers are investigated.Next,the spinnability of the fibers is analyzed by the properties of the fibers.According to the characteristics of PHBV/PLA fiber such as high brittleness,low fracture strength and elongation at break and friction force,the spinning process was designed reasonably and the technological parameters of smooth spinning were determined.Finally,the perfect yarn and spinning process parameters were illustrated from the measurement of the density,twist,hairiness,evenness and tensile strength of yarns.In summary,the following conclusions are obtained:(1)The cross section of PHBV/PLA fiber close to a circular and there are irregular protrusions and speckled cracks on the longitudinal surface and grooves parallel to the axial depth.The average linear density of the fibers is 1.66 dtex.There is little difference in fracture strength at room temperature and dry strength,the fracture strength at room temperature is 0.70 CN / dtex,elongation at break is 4.05%.The moisture regain is only 1.6%.The crimp performance and the friction performance are poor.The static friction coefficient is much smaller than the dynamic friction coefficient.But the antistatic performance is excellent with the volume specific resistance at 4.91 × 109.The limiting oxygen index is 31.66% and shows excellent flame retardancy.The bacteriostatic rate of Staphylococcus aureus is 87%,but it has no inhibitory effect on Escherichia coli.(2)The spinnability of PHBV/PLA is analyzed according to its basic properties.The linear density of yarn is designed by 28 tex.The blending ratio of PHBV/PLA and cotton is 100 / 0,35 / 65 and 50 / 50,respectively.The spinning method is chosed to ring spinning,and the blending mode is strip mixing.(3)Through carding process of PHBV/PLA/ cotton with different blending ratio,it is obtained that pure PHBV/PLA fiber can spinning birth sliver smoothly,and PHBV/PLA and cotton with different blending ratio can't.The optimum technological parameters of carding are as follows:the speed of cylinder,doffer and licker-in is 540 r/min,14 r/min and 600 r/min respectively,the spacing of cylinder / cover plate is 10 wire(0.254mm).At last,the spinning process of PHBV/PLA sliver and cotton sliver is carried out by using the model of two cotton sliver clamp PHBV/PLA sliver.The experiment scheme was designed by using frequency,twist and drafting ratio as variables,and six sets of yarns were spun successfully.It was concluded that there are six groups of process parameters can achieve smooth spinning,the blending ratio of one group of PHBV/PLA/ cotton and the other five groups of PHBV/PLA/ cotton was 65 / 35 and 50 / 50 respectively,which indicated that pure PHBV/PLA spinning could not be smoothly spun,and when the blending ratio of PHBV/PLA fiber exceeded 50%,the spinning difficulty increased and the spinnability decreased.(4)By testing the twist,hairiness,unevenness and strength of six groups of yarns,it was determined that six sets of yarns are meet the textile and garment requirements.One group was superior yarn,three groups of first-grade yarn,two groups of second-class yarn.And when the blending ratio of PHBV/PLA fiber is more than 50% after the adjustment of the spinning process of normal spun yarns,but also blended yarn quality is poor.At the same time,the optimum spinning process parameters is the blending ratio of PHBV/PLA and cotton is 50 / 50,the spinning frame frequency is 10 HZ,the speed of ring is 7214r/min,the speed of front thread is 9.017 m / min,the twist is 800 twist / m,the drafting ratio 1 is 60 and the drafting ratio 2 is 62.