摘要
以牌号为LX175、2500HP的聚乳酸(PLA)为原料,通过熔融纺丝制备大直径PLA初生丝,并经过2次拉伸和热定型处理得到直径为0.17~0.22 mm的大直径PLA单丝,研究了拉伸和热定型对PLA单丝的热学性能、结晶行为及力学性能的影响。结果表明:LX175、2500HP PLA初生丝为无定形态,经过2次拉伸后,得到的PLA单丝结晶度提高,力学性能提升;经热定型后,不同总拉伸倍数(6.50,7.50,8.25)下的PLA单丝的结晶度没有明显变化,LX175 PLA单丝在总拉伸倍数为7.50及2500HP PLA单丝在总拉伸倍数为8.25时有最大结晶度,分别为48.0%和62.0%;通过拉伸和热定型可以增大PLA单丝的晶粒尺寸,进而提高其结晶度;经热定型后,PLA单丝力学性能进一步完善,在总拉伸倍数为6.50时,LX175 PLA单丝和2500 HP PLA单丝均有最大的拉伸强度,分别为454 MPa和372 MPa。
Large-diameter polylactic acid(PLA)as-spun filaments were prepared using PLA LX175 and 2500HP as raw materials by melt spinning and were produced into large-diameter PLA monofilament with the diameter of 0.17-0.22 mm after twice drawing and heat setting treatment.The effects of drawing and heat setting treatments on the thermal properties,crystallization behavior and mechanical properties of PLA monofilaments were studied.The results showed that as-spun LX175 and 2500HP PLA filaments were of amorphous morphology and were drawn twice into PLA monofilaments,and the crystallinity and mechanical properties of the obtained PLA monofilaments were improved;the crystallinity of PLA monofilament under different total draw ratios(6.50,7.50,8.25)did not change significantly after heat setting,and the maximum crystallinity were 48.0%and 62.0%,respectively for LX175 PLA monofilament at a total draw ratio of 7.50 and 2500HP PLA monofilament at a total draw ratio of 8.25;the crystal size and crystallinity of PLA monofilament could be increased by drawing and heat setting;and the mechanical properties of PLA monofilament were further improved after heat setting,and LX175 PLA monofilament and 2500HP PLA monofilament had the maximum tensile strength of 454 MPa and 372 MPa respectively at a total draw ratio of 6.50.
作者
杨青山
毛雯雯
李大伟
邓炳耀
刘庆生
YANG Qingshan;MAO Wenwen;LI Dawei;DENG Bingyao;LIU Qingsheng(Key Laboratory of Eco-textiles of Ministry of Education,Jiangnan University,Wuxi 214122)
出处
《合成纤维工业》
CAS
2021年第5期1-7,共7页
China Synthetic Fiber Industry
基金
中国纺织工业联合会应用基础研究项目(J202008)
中国博士后科学基金面上项目(2019M651699)。
关键词
聚乳酸纤维
大直径单丝
熔融纺丝
拉伸
热定型
结晶性能
力学性能
polylactic acid fiber
large-diameter monofilament
melt spinning
drawing
heat setting
crystallization properties
mechanical properties
