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951.
Miscibility between acrylic copolymers and tackifier resins are investigated in terms of phase diagrams, and the probe tack of the blends are measured as a function of both temperature and rate of separation in order to obtain the master curves. It is found that the probe tack of the pressure sensitive adhesives are closely related to the miscibility between the components. The master curves of the miscible blends shift along the X(rate)-axis according to the change of Tg of the bulk materials with a gradual variation of the peak heights. However, those of the immiscible blends will not shift along the X(rate)-axis, but the magnitude will decrease with increase of a dispersed phase. 相似文献
952.
Blends of uncrosslinked styrene-butadiene rubber (SBR) with a terpene tackifier resin or a naphthenic oil have been characterized, and their autohesion and cohesion determined using a T-peel geometry. SBR/oil blends are homogeneous at all proportions, while SBR/resin blends, based on DSC and DMA analysis, undergo bulk phase separation at about 50% resin. However, migration of tackifier to the surface region is proposed at much lower resin contents. Compositions diluted with oil have autohesion similar to the neat SBR. This is attributed to compensating effects; although oil hastens self-bond formation by increasing chain mobility, this is nearly equally balanced by more facile chain separation during bond rupture. In short, oil-diluted compositions are soft and weak. On the other hand, SBR compositions containing small amounts of resin have high autohesion. Resin-diluted specimens deform easily at low strain, just as those containing oil, but intertwined chains of the former have greater resistance to separation, due at least in part to higher glass transition temperatures. It is proposed that autohesion is further enhanced by migration of tackifier to the surface. This causes SBR/resin compositions to be both soft and strong-a necessary condition for high autohesion. 相似文献
953.
十四醇聚氧化烯烃醚琥珀酸单酯磺酸盐的表面活性研究 总被引:6,自引:0,他引:6
合成了一系列十四醇聚氧乙烯醚和聚氧丙烯醚琥珀酸单酯磺酸盐,比较了其临界胶束浓度、润湿力、起泡力等表面活性 相似文献
954.
T406型脱氯剂的研制与工业应用 总被引:1,自引:1,他引:1
报导了型脱氯剂的研制、性能试验和工厂运行结果。与国内外常见同类脱氯剂的对比试验及工业应用表明, 由化工部西北化工研究院开发研制的这一新型脱氯剂具有抗压碎强度高, 净化度高, 氯容量高的特点, 可以在常温下用于气相和液相原料中氯化物的脱除。即使在低温(4℃)下, 净化后原料中氯降至左右的情况下抓容量仍高达18%以上。该脱氯剂还能同时脱除原料中的硫。T406型脱氯剂已工业应用于混合二甲苯和氢原料的脱氯, 使用效果良好。 相似文献
955.
德士古气化炉的提温操作 总被引:2,自引:0,他引:2
通过更换煤种使生产消耗得到了大幅度降低,生产能力得到了较大的提高,但渣中可燃物较设计指标提高了2-3倍,为此进行了提高炉温的试验,考察渣中可燃物随炉温的变化关系,则时考核不同渣中可燃物含量下的氧耗和煤耗。 相似文献
956.
在热媒温度控制系统中以熔体温度作为主参数,组成串极调节系统。投入运行后,熔体温度稳定,调节阀动作平稳,效果良好。 相似文献
957.
Li-Piin Sung Joan Jasmin Xiaohong Gu Tinh Nguyen Jonathan W. Martin 《Journal of Coatings Technology and Research》2004,1(4):267-276
Laser scanning confocal microscopy (LSCM) has been used to characterize the changes in film thickness and local surface morphology
of polymer coatings during the UV degradation process. With the noninvasive feature of LSCM, one can obtain thickness information
directly and nondestructively at various exposure times without destroying the specimens or deriving the thickness values
from IR measurement by assuming uniform film ablation. Two acrylic polymer coatings were chosen for the study, and the physical
and chemical changes of the two systems at various exposure times were measured and analyzed. Those measurable physical changes
caused by UV exposure include film ablation, formation of pits and other surface defects, and increases in surface roughness.
It was found in both coatings that changes in measured film thickness by LSCM were not correlated linearly to the predicted
thickness loss using the changes in the CH band obtained by the Fourier Transform Infrared (FTIR) spectroscopy measurements
in the later degradation stages. This result suggested it was not a uniform film ablation process during the UV degradation.
At later stages, where surface deformation became severe, surface roughness and profile information using LSCM were also proven
to be useful for analyzing the surface degradation process
Presented at the 81st Annual Meeting of the Federation of Societies for Coatings Technology, November 13–14, 2004 in Philadelphia,
PA. 相似文献
958.
A number ofcis andtrans quatenary ammonium salts were synthesized from jojoba oil. All derivatives were found to be surface active agents, i.e.,
they reduced the surface tension to 35 dynes/cm−1, at very low concentrations. The relationship between the surface activity and the molecular structure is discussed. 相似文献
959.
介绍了 6 m大容积焦炉由冷态到转入正常加热温度的烘炉操作过程中 ,按照一定的升温曲线 ,通过对焦炉热工和炉体膨胀的科学管理 ,确保新建焦炉顺利由冷态过渡到生产状态。 相似文献
960.