共查询到19条相似文献,搜索用时 468 毫秒
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抑制菱镁制品返卤泛霜的实验研究 总被引:2,自引:0,他引:2
在以往的研究中,大多采用无机改性剂或有机改性剂进行研究,进而导致菱镁制品的试验研究停留在一定的水平。试验研究采用加入有机高分子改性剂和无机改性剂Na3PO4复合改性剂,先用不同剂量的有机高分子改性剂,找出有机高分子改性剂的最佳含量,再用不同剂量的无机改性剂Na3PO4与其混合使用,从而找出复合改性剂的最佳配方。实验结果表明,磷酸盐可以提高菱镁水泥的抗水性,复合效果更佳。对添加多种新型混合活性改性剂的试验研究,使菱镁制品返卤泛霜的现象得到了明显的抑制。 相似文献
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本文概述了改性剂品种,以及它们在硬质PVC中作为冲击改性剂、在软质PVC中作为永久增塑剂的应用研究,并介绍了它们的性能情况,对应用改性剂时相应的工艺作了探索,可供PVC配方设计和工艺人员参考。 一、改性剂的品种 改性剂通常包括加工改良剂和冲击改性 相似文献
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改性淀粉/聚乙烯共混物的性能研究 总被引:6,自引:0,他引:6
采用5种淀粉改性剂即改性剂A,改性剂B,改性剂C,改性剂D和改性剂E,研究了改性淀粉/PE共混物与PE的相容性,热性能和力学性能。结果表明,改性淀粉与PER的相容性都有不同程度的改进,以改性剂A最为明显,接触角由未改性淀粉的29度提高到44度。电镜分析表明,聚乙烯中淀粉颗粒分散均匀,界面模糊。 相似文献
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聚氯乙烯抗冲改性剂和加工改性剂现状 总被引:2,自引:0,他引:2
介绍了ABS、ACR、CPE、EVA等PVC抗冲改性剂和加工改性剂,并对其性能分别进行了讨论,结果认为ACR抗冲改性剂效果优异,应加速研究和开发ACR改性剂。同时对PVC抗冲性剂和加工改性剂的市场应用状况和技术进展也进行了介绍。 相似文献
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采用不同方法[包括EP(环氧树脂)的pH值调节法、EP中添加改性剂法和改性剂吸附包覆纳米TiO2法等]对纳米TiO2在EP中的分散性进行了研究。结果表明:上述改性方法均能促进纳米TiO2在EP中良好分散:当EP的pH值为3时,相应胶粘剂的剪切强度比pH值未调节体系提高了11.46%;采用EP中添加改性剂法,并且当改性剂为SDBS(十二烷基苯磺酸钠)时,相应胶粘剂的剪切强度比无改性剂体系提高了6.7%;采用改性剂吸附包覆纳米TiO2法,并且当改性剂为SDS(十二烷基磺酸钠)、KH-560(硅烷偶联剂)和SDBS时,相应胶粘剂的剪切强度比无改性剂体系分别提高了41.7%(SDS)、16.4%(KH-560)和9.4%(SDBS)。 相似文献
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Polylactic acid (PLA) was melt‐blended with different amount (0 to 50 wt %) of a commercially available ethylene acrylate copolymer impact modifier. PLA/impact modifier blends were prepared via an internal mixer and compression molded into test specimens. The thermal, mechanical, and morphological properties of the blends were investigated. The addition of impact modifier decreased the ability of PLA to crystallize and/or recrystallize. The degree of crystallinity of PLA decreased while the cold crystallization temperature shifted to higher temperatures with increasing the impact modifier content. PLA/impact modifier blends were partially miscible. This was confirmed by the dynamic mechanical analysis (DMA) tests. With increasing the impact modifier content, the blends showed some improvement in the elongation at break and notched impact strength indicating the toughening effects of the impact modifier. In contrast, the yield stress and tensile modulus decreased with the increase in the impact modifier content. Scanning electron microscopy (SEM) micrographs revealed that the toughening mechanisms among others involved shear yielding or plastic deformation of the PLA matrix induced by interfacial debonding between the PLA and the impact modifier domains. PLA with 30 wt % impact modifier showed comparable yield stress and tensile modulus and better elongation at break and impact strength (+90%) than those of polypropylene (PP). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 123:2715–2725, 2012 相似文献
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介绍了采用物理共混改性提高ABS树脂的抗冲击性的方法,确定了抗冲击改性剂的种类和用量,并研究了改性剂对ABS的抗冲性能、耐热性能和熔融流动性能的影响。 相似文献
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王英 《现代塑料加工应用》2002,14(2):36-40
研究了冲击改性剂种类和添加量对硬质PVC/木纤维复合材料机械性能的影响。硬质PVC/木纤维复合材料的抗冲击性与冲击改性剂的种类和含量有关,当冲击改性剂的种类和浓度选择得当时,硬质PVC/木纤维复合材料既不降低拉伸强度,又可提高冲击韧性,MBS和ACR类改性剂在提高硬质PVC/木纤维复合材料的抗冲击性方面优于CPE。 相似文献
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An evaluation of supercritical fluid extraction as an analytical tool to determine fat in canola,flax, solin,and mustard 总被引:1,自引:0,他引:1
Supercritical fluid extraction (SFE) with carbon dioxide was used to extract oil from soft oilseeds (flax, solin, canola,
and mustard). Oil content determinations from the SFE method AOCS Am 3–96, with and without ethanol as a modifier, were compared
to results obtained with an exhaustive extraction using petroleum ether (FOSFA as in AOCS Am 2–93). Without the modifier,
oil recoveries using SFE were 10 to 15% lower than oil contents by the FOSFA method for the flax and canola samples. For mustard,
the oil recoveries by SFE were about 20 to 30% lower than oil contents by the FOSFA method. In the presence of the modifier,
oil recoveries for flax and canola were about 3% lower than the FOSFA recoveries. Varying the time, temperature, and amount
of modifier (ethanol) showed that recoveries increased with time, pressure, temperature, and amount of modifier independently
of the oilseeds tested. Kinetics of the SFE extraction showed that the oil recoveries increased with the extraction time and
reached a plateau after 60 min. Multiple extractions (2×30 min), however, gave better recoveries than a single extraction
for the same amount of time (60 min). The best results were obtained using multiple extractions without modifier or a combination
of multiple extractions first without and then with 15% modifier. Under these last two conditions, oil recoveries were close
to 100% for flax, solin, and canola, but mustard oil recoveries were still 10% lower than recoveries using the FOSFA method.
Mustard samples gave the lowest oil recovery from SFE when compared to FOSFA method recoveries whatever conditions were tested,
suggesting a matrix effect on the oil recovery. The acyl lipid content of the various extracts was studied using the sum of
all FA expressed as TAG as a measure of acyl lipid extraction. The acyl lipid contents of the extracts were close to 100%
when no modifier was used during the SFE. In the presence of modifier, the acyl lipid contents of the extracts were 10 to
15% lower than the results obtained without modifier. The amount of acyl lipid in the extract decreased as the quantity of
modifier increased. This suggests that increasing the ethanol modifier increased the amount of polar compounds extracted without
significantly increasing the total amount of lipids. The FA profiles were constant throughout the various extraction procedures. 相似文献