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研究了聚甲醛供聚酰胺(POM/COPA)二元及聚甲醛/共聚酰胺/乙烯-醋酸乙烯酯共聚物(POM/COPA/EVA)三元共混物,探讨了COPA、EVA用量对共混体系性能的影响。结果表明,C1DPA的加入使共混物的熔融温度(Tm)增大;当COPA含量为4%(质量分数,下同)时,00PA能够较均匀地分散于POM基体中,共混物缺口冲击强度出现最大值,比纯聚甲醛提高了约63.3%,而拉伸强度变化不大,POM/COPA共混物具有较理想的综合力学性能。EVA的加入使共混物缺口冲击强度和拉伸强度均呈下降趋势。 相似文献
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聚甲醛的耐光稳定化研究 总被引:4,自引:0,他引:4
讨论了聚甲醛(POM)的光老化机理、光老化特征及各种添加剂对POM的光稳定化作用,以及添加剂配合法、其它聚合物单独添加法、其它聚合物配合法等对POM耐光稳定化的效果和相应的光稳定化机理。 相似文献
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将3种不同的超高摩尔质量聚乙烯(UHMWPE)和聚甲醛(POM)共混,制成POM自润滑材料,并研究了共混物的摩擦磨损性能。结果表明:采用自制的PP改性UHMWPE(M-UHMWPE)与POM共混,能有效提高POM的摩擦磨损性能;当M.UHMWPE质量分数为5%时,POM/M-UHMWPE共混物的摩擦系数从纯POM的0.32降低到共混物的0.16,磨痕宽度从POM的5.00mm下降为3.56mm;SEM分析表明,在摩擦过程中,M-UHMWPE向磨损界面转移形成磨屑,有效地隔离了两摩擦面的接触,起到了减摩耐磨剂的作用,明显降低了POM树脂的摩擦系数,提高了POM的耐磨损性能。 相似文献
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高抗冲POM/OOPA共混物的研制 总被引:2,自引:0,他引:2
研究了原料配比、制样工艺条件对聚甲醛/三元共聚酰胺(POM/COPA)共混物力学性能的影响,并用红外光谱仪、差热分析仪及扫描电镜对共混物中两相间存在的相互作用及共混物的微观形态结构进行了研究。结果表明COPA加入量及制样工艺条件对共混物的冲击强度有较大影响,共混物中POM与COPA分子间存在氢键作用。 相似文献
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改性脲醛树脂胶粘剂的研制 总被引:5,自引:0,他引:5
利用加入三聚氰胺、聚乙烯醇、淀粉等改性剂来改善脲醛胶的耐水性和耐老化性,同时降低游离甲醛的含量,使用时加入改性填料,既提高胶的剪切强度,又降低胶的成本。 相似文献
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采用挤出成型制备出了具有优异韧性的乙烯–丙烯酸甲酯共聚物(EMA)改性聚甲醛(POM),研究了EMA对POM热氧老化性能的影响。采用万能拉力机、广角X射线衍射仪和蠕变仪对不同老化时间的纯POM和EMA改性POM的力学性能、结晶性能及蠕变性能进行了对比分析。结果表明,EMA的加入明显提高了POM的韧性,当EMA质量分数为9%时,其改性的POM冲击强度和断裂伸长率分别比纯POM提高了13%和97%,而拉伸和弯曲强度仅下降了4.5%和8.0%,结晶度和耐蠕变性也略有下降。EMA的加入并没有劣化POM的热氧老化性能,随老化时间的增加,EMA改性POM的拉伸和弯曲强度、结晶度、蠕变性能变化趋势与纯POM基本相同,在30 d老化时间内,其冲击强度和断裂伸长率的下降幅度较大,但仍高于相同老化时间下的纯POM,且在老化早期,EMA改性POM的韧性仍高于未老化时的纯POM,表明其可应用于汽车方向盘轴承链等需要材料具有较好韧性的零件部位。 相似文献
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A series of new composite of polyoxymethylene/polyamide 6 (POM/PA 6) were synthesized by using ε‐caprolactam as a reactive solvent with POM soluble in it. Incorporating a small content of POM (1–4 wt %) into PA 6 led to a great improvement of impact resistance POM/PA 6. The effects of POM content on the mechanical, morphological, and thermal properties of the composites were investigated. Incorporating minor POM (1 wt %), disposed in finely dispersed level (about 1 μm), into PA 6 matrix can greatly reduce the crystallization rate and crystallinity of PA 6. Scanning electron microscopy measurements indicated that much microfibers with aspect ratio about 10 appeared with the addition of 3 wt % POM because of the change of phase separation mechanisms. As a result, with a small content of PA 66 (1–4 wt %) incorporated, the impact strength and elongation of POM/PA 6 were improved markedly, with retention of good tensile strength. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 335–339, 2006 相似文献
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The various properties of the blends of polyacetal (POM) with up to 20 wt.-% chemically surface-treated poly(tetrafluoroethylene) (CPTFE) were investigated and compared with those of POM/PTFE blends. The PTFE is added to POM to improve the wear properties, however, the mechanical properties of POM/PTFE blends decrease with increasing PTFE content, but tensile strength and Young's modulus of POM/CPTFE blends are more than 2 times higher than that of the POM/PTFE blends. SEM shows that the size of inherent agglomerative PTFE is in the range of 30 to 100 μm. The particle size of major CPTFE dispersed in POM is smaller than 1 μm. 相似文献
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超细Fe粉改性聚甲醛的研究 总被引:1,自引:0,他引:1
刘莉;孙立水;李少春;刘光烨 《中国塑料》2010,24(4):91-95
研究了超细Fe粉对聚甲醛(POM)的改性效果,结果表明:Fe粉粒径越小增强增韧效果越好,粒径为140 nm的Fe粉增强效果优于粒径为1 μm的Fe粉。分散剂TAS-2A的分散效果最好,其用量为Fe粉含量1.5 %~2.0 %时效果最佳。钛酸酯偶联剂处理Fe粉效果优于硅烷类偶联剂,其中钛酸酯偶联剂NDZ-201最适合POM/Fe复合材料,其用量为Fe粉含量的2.0 %时效果最好。Fe粉含量为4 %时,POM/Fe/ NDZ-201复合材料的冲击强度达到9.6 kJ/m2,较纯POM提高4.6 kJ/m2。 相似文献
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以改性纳米SiO2为填料,通过熔融共混工艺制备聚甲醛/纳米SiO2复合材料,对其力学性能、结晶行为及热稳定性进行了研究。结果表明:复合材料的拉伸强度和缺口冲击强度随着SiO2含量的增加呈先增大后减小的趋势,二者分别在SiO2质量分数为3%和1%时达到最大;而弹性模量的情况则有所不同,其随着SiO2含量的增加不断增大。DSC测试结果显示,纳米SiO2具有较好的形核作用,能够促进聚甲醛的结晶温度升高,但会抑制晶粒的生长,导致复合材料结晶度的降低。此外,纳米SiO2还能显著提高聚甲醛的热稳定性。与纯聚甲醛相比,复合材料的最大热分解温度在氮气和空气气氛下分别提高了约41.1℃和24.5℃。 相似文献
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用顺酐化EPDM增容的EPDM改性聚甲醛 总被引:3,自引:1,他引:3
以顺酐化三元乙丙橡胶(MEPDM)为增容剂,研究了EPDM对聚甲醛(POM)的共混增韧生。结果表明,MEPDM能明显改善POM与EPDM的相容性,使共混物分散相尺寸明显减少,分布更均匀,熔点和结晶度降低,缺口冲击强度提高。当POM/EPDM/MEPDM(质量比)为85/9/6时,共混物的缺口冲强度为10.2kJ/m^2。 相似文献
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以聚甲醛(POM)切片为原料,在200~210℃进行熔融纺丝制得POM长丝。利用DSC、Olympus偏光显微镜、单纱电子强力仪测定了POM纤维结晶度、熔点、取向度和纤维的机械性能;研究了后处理对POM纤维性能的影响以及拉伸对POM纤维耐酸碱性能的影响。结果表明:(1)POM纤维耐碱性良好,拉伸可以提高POM纤维结晶度、取向度、断裂强度以及耐酸性,但是使断裂伸长率减小;最佳拉伸温度在110℃左右,拉伸倍率在6~8之间。(2)热定形温度对POM纤维结晶度和熔点影响不大,延长热定形时间使POM结晶度、熔点降低;最佳热定形条件为在140℃下热定形4min。(3)经过拉伸热定形后的POM纤维的最大断裂强度和断裂伸长率分别为7.41cN/dtex和19.2%。 相似文献
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A plasma technique was applied to modify the surface of polytetrafluoroethylene (PTFE) fiber to improve the compatibility between PTFE and polyacetal (POM). This technique used argon (Ar) plasma to treat PTFE fiber first and then grafting the fiber with acrylic acid (AAc) by peroxidation. The Ar plasma‐treated PTFE (PPTFE) fiber and AAc‐grafted PPTFE (AAc‐g‐PPTFE) fiber were added into POM to increase the wear resistance and to decrease the friction coefficient of POM. The variables of the experiments were plasma treatment time, monomer concentration of AAc, and grafting time. The graft copolymer was characterized by Fourier transform infrared (FTIR) spectroscopy. The stress–strain behavior, impact strength, Taber wear factor, friction coefficient, and morphology of composites were also investigated. The properties of POM/PTFE composites could be successful modified by surface modification of PTFE in this investigation. The impact strength of POM/AAc‐g‐PPTFE composites was more than twice of that of POM/PTFE composites. The Taber wear factor and friction coefficient of POM/AAc‐g‐PPTFE composites decreased markedly. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 800–807, 2000 相似文献