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61.
Gina‐Gabriela Bumbu Cornelia Vasile Maria Cristina Popescu Hristea Darie Gabrielle Charlotte Chianu Gheorghe Singurel Adrian Carpov 《应用聚合物科学杂志》2003,88(11):2585-2597
The compatibility of the hydroxypropyl cellulose (HPC) with maleic acid–vinyl acetate copolymer in the solid state was studied by thermogravimetry, thermo‐optical analysis, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and optical microscopy. It was established that physical interactions are prevalent in blends with a high content of HPC, whereas chemical interactions predominate in blends with a medium and low content of HPC. By increasing the temperature, the thermochemical reactions are favored. Thermal properties are dependent on the mixing ratio of the components. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2585–2597, 2003 相似文献
62.
粘帚霉可湿性粉剂助剂的初步研究 总被引:3,自引:0,他引:3
可湿性粉剂是生物农药的重要剂型。通过平板培养法,测定菌落形成单位数(cfu值1,开展了可湿性粉剂多种常用助剂对高效生防真菌粉红粘帚霉67.1菌株孢子的生物学相容性研究。所试载体中,滑石粉等4种处理与对照没有显著性的差异,对粘帚霉孢子活力影响不明显;所试润湿分散剂中,木质素磺酸钙与对照没有显著性差异,对粘帚霉孢子活力影响不明显;所试紫外保护剂均对孢子活力无显著影响,但在紫外灯照射3min的条件下,只有腐植酸和糊精能有效保护孢子活力;常用稳定剂CMC—Na(羧甲基纤维素钠)对孢子活力无影响。上述多种与粘帚霉孢子具良好生物学相容性助剂的确定,为粘帚霉可湿性粉剂的研究提供重要依据。 相似文献
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The viscoelastic behavior, thermodynamic compatibility, and phase equilibria in block copolymer-based pressure-sensitive adhesives were investigated. The block copolymers investigated were: (1) polystyrene-block-polybutadiene-block-polystyrene (SBS) copolymer (KRATON® D-1102, Shell Development Company) and (2) polystyrene-block-polyisoprene-block-polystyrene (SIS) copolymer (KRATON® D-1107, Shell Development Company). The tackifying resins investigated were: (1) WINGTACK® 86 (Goodyear Tire & Rubber Company) and (2) PICCOTAC® 95BHT (Hercules Inc.). Samples of various compositions were prepared by a solution-casting method with toluene as solvent. Measurements of dynamic storage modulus (G'), dynamic loss modulus (G'), and loss tangent (tan δ) were taken, using a Rheometrics Mechanical Spectrometer. It was found that: (1) both WINGTACK 86 and PICCOTAC 95BHT were equally effective in decreasing the plateau modulus (GON), and increasing the glass transition temperature (Tg) of the polyisoprene midblock of KRATON 1107; and (2) WINGTACK 86 was very effective in decreasing the GON and increasing the Tg of the polybutadiene midblock of KRATON 1102, whereas PICCOTAC 95BHT was not. The observed difference between WINGTACK 86 and PICCOTAC 95BHT in decreasing the GON and increasing the Tg of the polybutadiene midblock of KRATON 1102, whereas PICCOTAC 95BHT was not. The observed difference between WINGTACK 86 and PICCOTAC 95BHT in decreasing the GON and increasing the Tg of the polybutadiene midblock of KRATON 1102 (perhaps to SBS block copolymers in general) is explained by the values of the interaction parameter for WINGTACK 86 and KRATON 1102, and for PICCOTAC 95BHT and KRATON 1102. The interaction parameter was determined, using the piezoelectric quartz sorption method. Phase diagrams were constructed for the four block copolymer/tackifying resin systems investigated, using information obtained from both dynamic viscoelastic measurements and optical microscopy. It was found that when mixed with KRATON 1102, PICCOTAC 95BHT formed separate domains whereas WINGTACK 86 did not over the range of concentrations and temperatures investigated. This confirms the evidence obtained from two other independent experimental techniques, namely, dynamic viscoelastic measurements and the piezo-electric sorption method. We have concluded from the present study that PICCOTAC 95BHT is not as an effective tackifying resin as WINGTACK 86, when each is mixed with KRATON 1102. It is pointed out further that information on the order-disorder transition temperature Tr, which was determined from a rheological technique proposed by us, is valuable in determining optimal processing conditions for block copolymer-based pressure-sensitive adhesives. 相似文献
65.
通过高分子合金化,以L-S相转化法制备了PVC/PMMA非对称型合金微滤膜,考察了铸膜液结构对微滤膜结构与性能的影响.结果表明:随聚合物浓度、铸膜液温度升高合金膜水通量降低,平均孔径减小;增大PMMA含量,水通量上升,平均孔径增大;随添加剂量的增加,合金膜水通量上升,平均孔径减小. 相似文献
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Ink‐eliminated sludge flour (IESF), waste residue from the recycling treatments of waste paper, was utilized as a new kind of filler to reinforce polypropylene (PP) in this research work. Different coupling agents, including maleated anhydride grafted PP (MAPP), stearic acid (SA), and titanate (NDZ‐101), were used to increase the compatibility between IESF and PP. By using different measurements, the microstructure, morphology, thermal behaviors, and mechanical properties of the IESF/PP composites were investigated in detail. It was found that IESF, as a nucleation agent, not only induced the crystallization orientation of PP but also accelerate the crystallization rate of PP. Just as indicated in the experiments, the presence of IESF has shown the advantages of increasing the dimensional stability, the hardness and the flexural property, and the presence of coupling agents has a favorable effect on the improvement of dimensional stability. Moreover, the coupling agent has minor influence on the mechanical property, even causes some decrease in the impact strength. Among these three coupling agents, MAPP is found to be the best coupling agent for increasing the interfacial adhesion between IESF and PP, and the MAPP addition makes the PP composite possess the quickest crystallization rate and greatest tensile strength. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 513–520, 2003 相似文献
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Silyl‐crosslinked urethane elastomer modifying epoxy resin has drawn much interest. Here the triethoxysilyl‐terminated polycaprolactone elastomer (PCL‐TESi) modifying diglycidylether of bisphenol A epoxy resins (DGEBA) system was chosen, and then the effect of the type of curing agent on the phase structure of the studied epoxy resin system was investigated. The modified systems were obtained with different phase structures by varying the formulations of the curing agent. It was experimentally shown that with the addition of aminosilane (KBE‐9103), the crosslinked density was greatly increased. The cured system also showed from SEM and TEM analysis that addition of KBE‐9103 increased the compatibility between the PCL‐TESi and DGEBA, which made the ductility of the system decrease, but also indicated from TEM that addition of much KBE‐9103 made the reacted silicone particles coagulate each other. The state of phase separation from TEM in the cured system was theoretically explained. These would serve the deeper studies of the mechanism of silyl‐crosslinked urethane elastomer modifying epoxy resin in the future. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 611–619, 2005 相似文献