摘要
以热塑性聚氨酯(TPU)、单层纳米石墨烯(GR)通过溶液与熔融共混并用的方法制备TPU/GR共混物,利用不同牵引速度纺丝制得不同直径的TPU/GR复合纤维,对其进行超临界二氧化碳微孔发泡,制得发泡TPU/GR复合纤维,探究了GR在TPU中的分散性,纤维尺寸和GR含量对发泡TPU/GR复合纤维泡孔结构及力学性能的影响。结果表明:GR在TPU体系中具有良好的分散形态及较高的二氧化碳气体阻隔性能;当发泡TPU/GR复合纤维直径为200μm时,随着GR含量的增加,纤维的发泡面积逐渐变大,泡孔直径呈现先减少后增加的趋势;对于直径为500μm的发泡TPU/GR复合纤维,随着GR含量的增加,纤维的泡孔直径逐渐变小,泡孔密度逐渐增加,即当加入质量分数为5%的GR,纤维泡孔直径由原来未加GR时的3. 78μm降低至1. 97μm,泡孔密度由原来的未加GR时4. 93×10~9cells/cm~3增加至2. 42×10~(10)cells/cm~3。
Thermoplastic polyurethane( TPU)/graphene( GR) composites were prepared from TPU and GR by a solution and melt blending,from which TPU/GR composite fibers with different diameter were fabricated at different drawing rate. Subsequently,foamed TPU/GR composite fibers were prepared by a batch foaming process using supercritical carbon dioxide as a foaming agent. The effects of the dispersity of GR in TPU,fiber dimension and GR content on the microcellular structure and mechanical properties of foamed TPU/GR composite fiber were studied. The results showed that GR sheets had a favorable dispersion morphology in TPU matrix and a relatively high carbon dioxide gas barrier property; the foaming area of the fiber was gradually increased and the cell diameter was decreased and then increased with the increase of GR when the foamed TPU/GR composite fiber was 200 μm in diameter; the cell diameter was gradually decreased and the cell density was gradually increased with the increase of GR when the foamed TPU/GR composite fiber was 500 μm in diameter; and the cell diameter of the fiber was decreased from 3. 78 μm to 1. 97 μm and the cell density was increased from 4. 93 × 10~9 cells/cm~3 to 2. 42 × 10~(10) cells/cm~3 when 5% GR was added by the mass fraction.
引文
[1]张艳.超高分子量聚乙烯纤维在防弹和防刺材料方面的应用[J].产业用纺织品,2010,28(10):32-39.
[2]王家豪,于燕华.导电纤维在针织物中的应用及抗静电性能研究[J].合成纤维,2006,35(9):43-45.
[3]汪家铭.高强高模聚乙烯纤维发展概况与应用前景[J].合成纤维工业,2008,32(3):25-30.
[4]Yeh S K,Liu Y C,Wu W Z,et al.Thermoplastic polyurethane/clay nanocomposite foam made by batch foaming[J].JCell Plas,2013,49(2):119-130.
[5]Dai Chenglong,Zhang Cailiang,Huang Wenyi,et al.Thermoplastic polyurethane microcellular fibers via supercritical carbon dioxide based extrusion foaming[J].Polym Eng Sci,2013,53(11):2360-2369.
[6]Cai Weiwei,Moore A L,Zhu Yanwu,et al.Thermal transport in suspended and supported monolayer graphene grown by chemical vapor deposition[J].Nano Lett,2010,10(5):1645-1651.
[7]Lee C,Wei X,Kysar J W,et al.Measurement of the elastic properties and intrinsic strength of monolayer graphene[J].Science,2008,321(5887):385-388.
[8]Balandin A A,Ghosh S,Bao Wenzhong,et al.Superior thermal conductivity of single-layer graphene[J].Nano Lett,2008,8(3):902-907.
[9]尚玉栋,李铁虎,朱新伟,等.石墨烯/聚合物复合材料的制备与研究进展[J].炭素技术,2016,35(2):1-5.
[10]Sauceau M,Fages J,Common A,et al.New challenges in polymer foaming:A review of extrusion processes assisted by supercritical carbon dioxide[J].Prog Polym Sci,2011,36(6):749-766.
[11]Di Yingwei,Iannace S,Maio E D,et al.Poly(lactic acid)/organoclay nanocomposites:Thermal,rheological properties and foam processing[J].J Polym Sci Part B Polym Phys,2010,43(6):689-698.