Preparation of nonwoven fabrics made from microfibers by using a carbon dioxide laser-thinning method

我们开发的二氧化碳激光减薄方法可以很容易地生产出非织造布，而不需要使用任何溶剂，如电纺和闪蒸纺丝。得到的非织造布由直径均匀的环形微纤维组成，没有熔融喷雾等液滴。以二氧化碳激光稀释法获得的微纤维为原料，制备了聚对苯二甲酸乙二酯(PET)非织造布。所制得的涤纶非织造布是由直径均匀、无液滴的环形微纤维制成的。通过控制进入空气射流的气流速度和进入激光照射点的原始纤维的供应速度，可以改变纤维直径。随着风量的增加和送风速度的降低，纤维直径减小，双折射增大。将激光辐照制得的超细纤维以4.8W cm~(-2)的功率密度作用于S_S=0.15mmin~(-1)的原纤维，以30 L min~(-1)的空气流量拖动，得到最细的超细纤维，直径为3.6 pm。所制得的PLLA非织造布是由直径均匀、无液滴的环形微纤维制成的。纤维直径可以通过控制进入空气射流的空气流量、进入激光照射点的原始纤维的供应速度和激光功率强度来改变。随着风量的增加和送风速度的降低，纤维直径减小，双折射增大。将功率为66W cm~(-2)的激光辐照制得的超细纤维，在S·S=0.1m·min的条件下，以30 L·min~(-1)的空气流量拖动，得到了直径为3.4μ~(-1)m的最细微纤维。

A carbon dioxide (CO_2) laser-thinning method developed by us could easily produce the nonwoven fabrics without using any solvent such as electrospinning and flashspinning. The obtained nonwoven fabric was composed of the endless mircofibers with a uniform diameter without droplets such as the meltblowing.Poly(ethylene terephthalate) (PET) nonwoven fabric was prepared from microfibers obtained by using a carbon dioxide laser-thinning method. The PET nonwoven fabric obtained was made of the endless mircofibers with a uniform diameter without droplets. The fiber diameter can be varied by controlling an airflow rate into the air jet and a supplying speed of an original fiber into a laser-irradiating point. The fiber diameter decreased, and its birefringence increased as the airflow rate increased and the supplying speed decreased. When the microfiber prepared by irradiating the laser operated at a power density of 4.8 W cm^<-2> to the original fiber supplied at S_s=0.15 m min^<-1> was dragged at an airflow rate of 30 L min^<-1>, the thinnest microfiber with a diameter of 3.6 pm was obtained.Poly(L-lactic acid) (PLLA) nonwoven fabric was prepared from microfibers obtained by using a carbon dioxide laser-thinning method. The PLLA nonwoven fabric obtained was made of the endless mircofibers with a uniform diameter without droplets. The fiber diameter can be varied by controlling an airflow rate into the air jet, a supplying speed of an original fiber into a laser-irradiating point, and laser power strength. The fiber diameter decreased, and its birefringence increased as the airflow rate increased and the supplying speed decreased. When the microfiber prepared by irradiating the laser operated at a power strength of 66 W cm^<-2> to the originalfiber supplied at S_s=0.1 m minwas dragged at an airflow rate of 30 L min^<-1>, the thinnest microfiber with a diameter of 3.4 μm was obtained.