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1.
介绍了草酸国内外生产现状,并对其市场行情,价位变动及前景进行了分析,表明其市场容量有增无减,建议要积极开拓国际市场。 相似文献
2.
邻法苯酐生产装置运行过程中产生大量顺酸尾水,通过转型、脱色、过滤、结晶等工序,将顺酸尾水加工处理,可以制得富马酸产品,母液水循环利用,不外排,既为企业创造经济效益,又达到治理环境目的。 相似文献
3.
本文合成了二甲基二烯丙基氯化铵-丙烯酸-丙烯酰胺-2-丙烯酰胺基-2-甲基丙磺酸多元共聚物。并对该共聚物在泥浆中的降滤失效果及其防塌能力进行了初步评价。 相似文献
5.
通过制备有机改性蒙脱土(MMT),共混改性乙烯-醋酸乙烯共聚物为主体的无卤膨胀阻燃电缆材料,发现改性MMT与聚磷酸铵(APP)/季戊四醇(PER)/三聚氰胺(MEL)三元膨胀阻燃剂(IFR)之间有力学和阻燃协效作用,能同时提高塑料的力学和阻燃性能。 相似文献
6.
本文讨论了分别用顺酐和反酸与聚酯合成不饱和聚酯树脂的反应机理,并分析了二种树脂体系固化放热曲线出现差异的原因在于固化交联时不饱和双键的活性不同。 相似文献
7.
弹性体与热塑性塑料共混得到的材料拥有较好的性能,其最大优势是成本低。共混体的发展,尤其是热塑性弹性体的发展,是因为提高了材料的韧性等机械性能,满足了各种场合的要求,改善了材料的加工性能,适应了市场的发展趋势(可回收性)。 相似文献
8.
本文介绍了一种低成本,综合性能优异的无纺布用自交联粘合剂--VAC/BA/ST/N-MA/AA共聚乳胶的制备方法,详尽地讨论了原材料的选择、单体配比及共聚工艺条件等对乳胶性能的影响,并确定了最佳配方和最佳工艺设计。 相似文献
9.
采用模压发泡成型工艺研究了乳胶/EVA/LDPE/PVC四元共混发泡片材的制备方法,着重讨论了橡塑比,发泡剂、交联剂、填充剂等用量对微孔发泡体物理机械性能的影响,并用电镜扫描观察了发泡体的断面构造,实验结果表明,该共混发泡体材料质轻,物理机械性能良好;该四元共混的工艺技术具有实用价值和经济效益。 相似文献
10.
介绍了一种丙烯酸丁酯/醋酸乙烯酯/丙烯腈/丙烯酸四元共聚乳液胶粘剂的制备方法,该胶具有良好的耐黄变性,可替代天然橡胶胶乳应用于EVA低发泡体与腈纶绒面布的复合。 相似文献
11.
Blends of 50 wt% of poly(vinyl chloride) (PVC) and 40 wt% of styrene butadiene rubber (SBR) with 10 wt% of acrylonitrile butadiene rubber (NBR) as the compatibilizer were prepared in a Haake mixer. An inversion of phase continuity was observed when the sulfur concentration was changed from 0.0 to 2.0 parts per hundred parts of resins (phr) in the blends containing an NBR with an acrylonitrile content of 29.5 wt% (NBR-29). The SBR phase, which is continuous in the unvulcanized blend, changes progressively into the dispersed phase as sulfur concentration increases. This is explained by the viscosity increase of the rubber caused by crosslinking. There is no phase inversion as a result of increasing sulfur concentration when the compatibilizer NBR-29 was replaced by an NBR with an acrylonitrile content of 40 wt% (NBR-40). The SBR phase is discrete in the unvulcanized blend with NBR-40 as the compatibilizer. A change in phase continuity occurs during processing of the vulcanized PVC/NBR-29/SBR (50/10/40) blends. A torque peak in the torque curve during processing is correlated to the transition of the PVC phase continuity. There is a gradual increase in the torque curve after the torque peak. The rubber particle size decreases as a result of such a post-peak increase in the torque. The torque peak and the post-peak increase in the torque are absent in the case of the binary blends (PVC/NBR and PVC/SBR). The post-peak increase in the torque is attributed to the interfacial reaction between SBR and NBR that resides in the PVC phase. A novel method developed recently was applied to study the interface development during processing. An interface with a higher rubber concentration develops during processing of the compatibilized blends. 相似文献
12.
The mechanical properties of poly(vinyl chloride) (PVC)/styrene-butadiene rubber (SBR) blends compatibilized by acrylonitrile-butadiene rubber (NBR) were studied. A sulfur curing system was employed to crosslink the rubber of the blends. In the case of the blends without any curing agents, an increase in NBR content did not improve the tensile strength and elongation-at-break. However, a significant improvement in the mechanical properties was observed when NBR was added as a compatibilizer and the blend was vulcanized. In the PVC/NBR/SBR (50/10/40) blends, the tensile strength and elongation-at-break increased with an increase in sulfur concentration. This improvement was attributed to covulcanization between NBR and SBR. The fracture toughness of PVC/NBR/SBR (50/10/40) blends was characterized by the critical strain energy release rate, G c. In the case of the PVC/NBR-29/SBR (50/10/40) blends, an increase in sulfur concentration resulted in a dramatic increase in G c. However, the G c value of PVC/NBR-40/SBR (50/10/40) blends decreased with an increase in sulfur concentration owing to the brittle behavior of one of the blend components—the PVC/NBR-40 (50/10) phase. 相似文献
13.
Blends of styrene-co-butadiene rubber (SBR) and acrylonitrile-co-butadiene rubber (NBR) were prepared and their rheological and mechanical properties were examined. The effect of the addition of 5 phr of poly acrylonitrile as compatibilizer on the compatibility of the rubber blend was studied. Ultrasonic and scanning electron microscopy (SEM) techniques were used to assess the degree of compatibility of the blend. The results revealed that the use of the prepared compatibilizer has significantly resulted in the clear stability of the cure rate index (CRI) of the blends and that the tensile strength was improved at (50/50) SBR/NBR blend. The degree of compatibility was enhanced to a great extent. 相似文献
14.
In this article, we discuss the effect of a compatibilizer for binary blends on the properties of ternary blends composed of high‐density polyethylene (HDPE), polypropylene (PP), or polystyrene (PS) and poly(vinyl chloride) (PVC) virgin polymers with a simulated waste plastics fraction. Chlorinated polyethylene (CPE), ethylene–propylene rubber (EPR), and their 1/1 (w/w) mixture were tested as compatibilizers for the HDPE/PP/PVC ternary blend. CPE, styrene‐ethylene‐propylene block copolymer (SEP), or their 1/1 (w/w) mixture were tested as compatibilizers for the HDPE/PS/PVC ternary blend. The composition of the ternary blends were fixed at 8/1/1 by weight ratio. The amount of the compatibilizer was 3 phr. Rheological, mechanical, and thermal properties were measured. For the 8/1/1 HDPE/PP/PVC ternary blends, the tensile strength was slightly decreased, but the impact strength was significantly increased by adding EPR, CPE, or their mixture. EPR exhibited the most significant impact modification effect for the ternary blends. In a similar way, for 8/1/1 HDPE/PS/PVC ternary blends, on adding SEP, CPE, or their mixture, the tensile strength was slightly decreased, but the impact strength was noticeably increased. It was found that the SEP worked much better as an impact modifier for the ternary blends than CPE or the SEP/CPE mixture did. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1048–1053, 2000 相似文献
15.
探讨了丁腈橡胶(NBR)中的结合丙烯腈质量分数、NBR/聚氯乙烯(PVC)(质量比,下同)、增塑剂邻苯二甲酸二辛酯(DOP)用量、PVC聚合度对NBR/PVC共混胶性能的影响,研究了NBR/低聚合度PVC共混胶的力学性能及加工流动性能。结果表明,随着NBR中结合丙烯腈质量分数的增加,NBR/PVC共混胶的耐油性能明显增强,力学性能也相应有所改善;NBR/PVC为80/20~60/40时.NBR/PVC共混胶的综合性能较好;DOP用量对NBR/PVC共混胶性能的影响不大;聚合度为700的PVC更适合于生产NBR/PVC共混胶,其力学性能、加工流动性能、耐老化性能与德国Bayer公司生产的牌号为Perbunan NT/VC3470B的NBR/PVC共混胶相当。 相似文献
16.
采用氯乙烯—丙烯酸丁酯(VC/BA)共混物作为聚氯乙烯(PVC)/高密度聚乙烯(HDPE)共混物的增容剂,通过冲击实验、拉仲实验、动态力学分析,系统地研究了共混体系性能与其结构之间的关系。通过Brabender流变仪测定了VC/BA共混物增容PVC/HDPE共混体系的流变性能。结果表明,VC/BA共混物是PVC/HDPE共混体系的良好增容剂。在一定范围内,VC/BA共混物与HDPE对PVC有协同增韧效应。vC/BA和HDPE的加入改善了PVC的塑化和流变性能 相似文献
17.
通过熔融共混法制备了HDPE/NBR(NBR为丁腈橡胶)二元共混物和HDPE/NBR/HDPE-g-MAH(MAH为马来酸酐)三元共混物,研究了其力学性能和相态结构。结果表明:对于极性不同的二元共混体系,加入15%(质量含量,下同)的NBR即可行到冲击强度为712.2J/m、相态结构为平行排列的丝状共混物;对于加有相容剂HDPE-g-MAH的三元共混体系,尽管冲击强度达到845.9J/m,但此时NBR加入量为25%,且相容剂的制备工艺繁琐,质量不好控制。 相似文献
18.
采用动态硫化方法制备高聚合度聚氯乙烯(HPVC)/SBR共混型热塑性弹性体,考察了单一组分相容剂「相容剂分别为NBR270、NBR P65、CPE和氢化苯乙烯-丁二烯、苯乙烯嵌段共聚物(SEBS)」、复合相容剂(SEBS/NBR和CPE/NBR)及交联程度对HPVC/SBR共混体系相容性的影响。结果表明,使用复合相容剂可明显改善HPVC/SBR共混物的性能;动态硫化在改善共混物力学性能方面起主要作 相似文献
19.
The present work focuses on the compatibization of styrene‐ co‐butadiene rubber (SBR)/acrylonitrile‐ co‐butadiene rubber (NBR) blends with dichlorocarbene modified styrene‐ co‐butadiene rubber (DCSBR) as a function of concentration of compatibilizer and composition of the blend. FTIR studies, differential scanning calorimetry and dynamic mechanical analysis reveal molecular level miscibility in the blends in the presence of compatibilizer. The formation of interfacial bonding is assessed by analysis of swelling behaviour, cure characteristics, stress–strain data and mechanical properties. These studies show that the compatibilizing action of DCSBR becomes more prominent as the proportion of NBR in the blend increases. The resistance of the vulcanizate towards thermal and oil ageing improved with compatibilization. The change in technological properties is correlated with the crosslink density of the blends assessed from swelling and stress–strain data. © 2001 Society of Chemical Industry 相似文献
20.
Polymer blends based on high-density polyethylene (HDPE) and acrylonitrile butadiene rubber (NBR) were prepared by a melt blending technique. The mixing parameters such as temperature, time, and speed of mixing were varied to obtain a wide range of properties. The mixing parameters were optimized by evaluating the mechanical properties of the blend over a wide range of mixing conditions. The morphology of the blend indicated a two-phase structure in which NBR phase was dispersed as domains up to 50% of its concentration in the continuous HDPE matrix. However, 70 : 30 NBR/HDPE showed a cocontinuous morphology. The tensile strength, elongation at break, and hardness of the system were measured as a function of blend compostion. As the polymer pair is incompatible, technological compatibilization was sought by the addition of maleic-modified polyethylene (MAPE) and phenolic-modified polyethylene (PhPE). The interfacial activity of MAPE and PhPE was studied as a function of compatibilizer concentration by following the morphology of the blend using scanning electron micrographs. Domain size of the dispersed phase showed a sharp decrease by the addition of small amounts of compatibilizers followed by a leveling off at higher concentrations. Also, more uniformity in the distribution of the dispersed phase was observed in compatibilized systems. The tensile strength of the compatibilized systems showed improvement. The mechanical property improvement, and finer and uniform morphology, of compatibilized systems were correlated with the improved interfacial condition of the compatibilized blends. The experimental results were compared with the current theories of Noolandi and Hong. © 1995 John Wiley & Sons, Inc. 相似文献
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