共查询到19条相似文献,搜索用时 78 毫秒
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超高分子量聚乙烯冻胶纤维萃取干燥工艺的研究 总被引:4,自引:0,他引:4
对超高分子量聚乙烯(UHMWPE)冻胶纤维进行萃取、干燥是改善其拉伸性能的主要技术关键.萃取、干燥的不同工艺条件都会较大地影响未拉伸干冻胶纤维的结构及其性能.其中主要有:萃取时间、萃取次数、干燥温度和干燥收缩率.本文借助电子强力试验仪、扫描电子显微镜(SEM)、X-射线衍射(WAXD、SAXS)和声速仪(SP)等对以三氯三氟乙烷(F113)、溶剂油120~#为萃取剂经不同萃取干燥工艺处理的冻胶纤维结构进行了测试,并对上述萃取、干燥处理过的冻胶纤维经超倍拉伸后所得的拉伸纤维性能进行了测试,得到了萃取、干燥的最佳工艺条件为:充分萃取、适温干燥、保持足够的干燥收缩率. 相似文献
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研究了超高相对分子质量聚丙烯(UHMWPP)的加入对超高相对分子质量聚乙烯(umfwPE)冻胶体系粘性行为、非牛顿指数、结构粘度指数的影响。结果表明:UHMWPP在UHMWPE/UHMWPP共混体系中起到了润滑剂的作用,使体系的表观粘度降低,非牛顿指数升高,结构粘度指数下降。其中,UHMWPP添加量为5%时,冻胶体系的可纺性最佳。 相似文献
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研究不同拉伸条件(热拉温度、拉伸比、拉伸速率、预热温度及时间,热定型温度及时间)对薄膜微孔的影响,并确定最优拉伸工艺为在预热温度100℃,定温时间5min,拉伸温度为110℃以及热定型温度120℃,定温时间5min下,热拉程度60%:先萃取后拉伸工艺,拉伸速率为30mm/min,先拉伸后萃取工艺,拉伸速率为10mm/min时,拉伸出的微孔数量较多且分布均匀。因此,为了得到孔径比较均匀且量较多的微孔膜,拉伸程度不宜过大,拉伸速率较小。 相似文献
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《合成纤维工业》2017,(4):5-10
采用双螺杆混炼挤出机溶胀、溶解和挤出纺丝技术制备超高相对分子质量聚乙烯(UHMWPE)冻胶纤维,经热管拉伸得到UHMWPE纤维,研究了冻胶纺丝工艺及后续热拉伸对UHMWPE纤维黏均相对分子质量(M_η)的影响,以及M_η与UHMWPE成品纤维力学性能、热性能、抗蠕变性能及耐磨性能的关系。结果表明:螺杆转速、溶解温度及溶液浓度变化引起的物料高温停留时间和受剪切强度变化对UHMWPE分子降解程度有很大的影响,超倍热拉伸工艺对UHMWPE分子降解影响不大;在UHMWPE溶解均匀的情况下,纤维强度、抗蠕变及耐磨性能随冻胶纤维M_η的增大而增大,且纤维结晶度增加,熔点升高;而UHMWPE溶解条件不佳时,冻胶纤维M_η最高,但纤维表面呈现不均匀凸起,纤维综合性能也变差。 相似文献
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国内外超高分子质量聚乙烯纤维的开发应用进展 总被引:2,自引:0,他引:2
介绍了超高相对分子质量聚乙烯(UHMWPE)纤维的性能及其国内外开发应用现状。对几家主要生产商,如DSM公司、Honeywell、日本东洋纺以及3家中国公司的生产及扩能情况进行了详细介绍。 相似文献
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Ultrahigh-molecular-weight polyethylene (UHMWPE) fibers have poor wetting and adhesion properties to polymer resins because of the inert surface of the fibers. In our previous study, a reactive nano-epoxy matrix, developed by making a modification on the matrix with reactive graphitic nanofibers (r-GNFs), showed improved wettability to UHMWPE fibers. In this work, fiber bundle pullout tests were conducted to evaluate the adhesion property between the UHMWPE fibers and the nano-epoxy matrices. Analysis of load-displacement curves from pullout tests shows that debonding initiation load and ultimate debonding load increased considerably, because of effective improvement of adhesion between the UHMWPE fibers and nano-epoxy matrix. Stress-controlled and energy-controlled models of interfacial debonding were applied for theoretical analyses. Results from ultimate IFSS, frictional shear stress, and critical energy-release rate are in good agreement with experimental results. Nano-epoxy matrix with 0.3 wt% r-GNFs shows effective improvement in terms of adhesion property between UHMWPE fiber and epoxy. 相似文献
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The effects of shear flow, temperature, and gel concentration on the rheological behavior of the ultrahigh-molecular-weight polyethylene (UHMWPE) gel in gel spinning process were investigated. The gel point was determined using parallel plate rheometry in rotation mode with controlled stress. Likewise, the flow curves at various temperatures were determined with controlled shear rate from 10−2 to 10 s−1. Whereas the shear storage modulus (G′) was obtained in oscillation mode with controlled strain from 1 to 100%. The result shows that the gel point of the UHMWPE gel increases with increasing gel concentration. The result from the strain sweep indicates that G′ of the gel is 1.5 × 103 Pa, and it exhibits a plateau at low strain, but it is reduced with increasing strain. At low shear rates, for temperatures above gel point, all flow curves exhibit a plateau, then go down with increasing shear rate. Studying contributions from UHMWPE gel concentration, temperature, and shear rate for rheological view, we found that spinning at 6% UHMWPE (MW : 1.4 × 106 g/mol) gel and 140°C gives the best effect on formation of fiber structure. © 1998 John Wiley & Sons, Inc. J. Appl. Polym. Sci. 70: 1009–1016, 1998 相似文献
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提取条件对竹纤维分级分离的影响 总被引:1,自引:0,他引:1
对竹纤维组分的分级分离工艺进行了研究。以乙醇为溶剂的分级分离条件:第一级分离中NaOH 2.1%、H2O2 1.5%,第二级分离中NaOH 2.4%、H2O2 2.0%,第三级分离中NaOH 2.4%、H2O2 1.0%。NaOH对各级半纤维素、木质素和纤维素的结构影响程度依次降低,而H2O2对各组分的结构影响不大。乙醇可同时提取木质素和半纤维素,而乙酸乙酯和丙酮不能提取半纤维素;乙酸乙酯提取的木质素具有较高的得率和纯度。丙酮和乙醇对纤维素、木质素的结构影响不大,而乙酸乙酯对纤维素和木质素的结构影响较大。 相似文献
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《Journal of Adhesion Science and Technology》2013,27(1-3):289-301
In order to investigate how coatings of glycerol affects atmospheric pressure plasma treatment, ultra high molecular weight polyethylene (UHMWPE) fibers were first pretreated with 0.2 and 0.6 mol/l glycerol solutions, respectively, and then were modified by an atmospheric pressure plasma jet (APPJ) using helium as the carrier gas with a flow rate of 20 l/min, discharge power of 30 W and a radio frequency of 13.56 MHz. After the plasma treatment, scanning electron microscopy (SEM) and atomic force microscopy (AFM) analysis revealed that the glycerol coated-APPJ treated samples possessed smoother surface than the APPJ directly treated samples. The X-ray photoelectron spectroscopy (XPS) analysis indicated that the changed content of oxygen containing groups on the surface of the glycerol coated groups compared with the non-glycerol coated group was mainly due to the remaining glycerol on the fiber surfaces. The water contact angle test revealed that the wettability of the glycerol coated-APPJ treated fibers decreased slightly in comparison with the APPJ directly treated fibers. Furthermore, the microbond pull-out test indicated that the interfacial bonding of the fiber to epoxy resin decreased when the fiber was pretreated with glycerol before plasma treatment. Therefore, it was concluded that the presence of glycerol on fiber surface weakened the effectiveness of APPJ treatment of UHMWPE fibers in improving the interfacial bonding to epoxy. This was mainly attributed to the consumption of plasma energy in etching the glycerol layer on the fiber surface and a weak interfacial layer due to the presence of residual glycerol. 相似文献