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1.
以马来酸酐(MAH)为单体、苯乙烯(St)为共单体、过氧化二异丙苯(DCP)为引发剂,采用溶剂热法分别制备了苯乙烯-丙烯腈共聚物(AS)接枝物AS-g-MAH以及AS-g-(MAH-St).利用红外光谱对接枝物进行了结构表征,证明MAH已经成功接枝在AS链上.并用反式滴定法测定了接枝率,讨论了引发剂用量、马来酸酐用量、反应温度、反应时间、反应物浓度和共单体用量对接枝率的影响.结果表明:随着引发剂用量的增加和反应时间的延长,接枝率先增大,然后趋于平稳;随着马来酸酐用量、反应温度和反应物浓度的增加,接枝率先增大后下降;共单体苯乙烯的加入对接枝率的提高有很大的促进作用.  相似文献   

2.
C_5石油树脂改性及其在胶黏剂中的应用   总被引:1,自引:0,他引:1  
根据接枝反应原理,采用马来酸酐为改性剂时C5石油树脂进行化学改性,提高其软化点,考察了马来酸酐质量分数、引发剂质量分数、反应温度和反应时间4个因素时产品软化点的影响.实验结果表明最佳改性条件:ω(马来酸酐)=0.9%,ω(引发剂)=0.1%,反应温度为200℃,反应时间为2.0h时,根据最佳反应条件制备胶黏剂效果较好.  相似文献   

3.
荆玲  李士斌 《天津化工》2008,22(1):38-40
以马来酸酐和苯乙烯为单体,采用固相接枝法将单体接枝到聚丙烯上;考察了反应温度、反应时间、引发剂用量、溶胀时间、粒径、单体物质的量比对接枝率的影响;红外光谱分析产物结构.结果表明:马来酸酐和苯乙烯接枝到聚丙烯上;最佳条件下接枝率为9.6%.  相似文献   

4.
功能化聚乙烯蜡的制备与表征   总被引:9,自引:0,他引:9  
用溶液接枝法制备了马来酸酐(MAH)和马来酸酐/苯乙烯(St)双单体接枝的功能化聚乙烯蜡(PEW),考察了反应时间、温度、引发剂、单体用量对产物接枝率的影响。结果表明,接枝改性的最佳条件为温度110-120℃,反应时间2h,原料质量比为m(PEW)/m(MAH)/m(BPO)r=100/4/2/0.3。用傅立叶红外光谱和差示扫描量热分析表征了接枝产物的结构。  相似文献   

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PEW-g-MAH的制备及其对PP/Talc的改性   总被引:2,自引:0,他引:2  
由线型低密度聚乙烯裂解反应制备了低相对分子质量聚乙烯蜡,考察了工艺条件的影响因素。得出了反应温度、反应时间与相对分子质量、熔点、软化点之间的关系。在锅中用熔融接枝法制备马来酸酐接枝聚乙烯蜡,研究了反应时间、温度、引发剂和马来酸酐用量对产物接枝率、接枝效率的影响。结果表明在引发剂质量分数0.1%、马来酸酐质量分数4%、反应温度150℃、反应时间3h的条件下,聚乙烯蜡的接枝率达到1.49%。接枝的聚乙烯蜡可作为一种新型偶联剂用于改性聚丙烯与填料复合材料的力学性能,使改性后的聚丙烯复合材料的悬臂粱缺口冲击强度提高了50%。  相似文献   

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研究了吉林石化高密度聚乙烯装置副产低分子量聚乙烯与马来酸酐(MAH)的融熔接枝反应,考察了单体、引发剂用量、反应时间、温度对接枝率的影响。马来酸酐接枝低分子量聚乙烯应用于PE/CaCO3体系的性能测试结果表明,接枝物可以起到偶联剂的作用,改善体系的性能。  相似文献   

7.
线性低密度聚乙烯反应挤出接枝马来酸酐的研究   总被引:8,自引:1,他引:8  
陈晓丽  李炳海 《塑料》2005,34(6):6-9
以过氧化二异丙苯(DCP)为引发剂,在双螺杆挤出机中进行了马来酸酐(MAH)熔融接枝线性低密度聚乙烯(LLDPE)的研究,用红外光谱表征了接枝反应的存在。考察了引发剂用量、单体用量、螺杆转速以及温度对接枝反应的影响,并探讨了苯乙烯(St)作共单体对接枝反应的影响。研究表明:在引发剂含量较低时,用苯乙烯作共单体能够显著提高接枝率。  相似文献   

8.
聚丙烯固相接枝马来酸酐的研究   总被引:1,自引:0,他引:1  
采用先降解后固相接枝技术,以马来酸酐(MAH)为单体,在自制的搅拌反应器中制备了马来酸酐接枝聚丙烯接枝物(PP-g-MAH),并对其结构进行了表征与分析,研究了接枝反应时间、接枝反应温度、引发剂质量分数和单体质量分数对接枝率的影响。结果表明,接枝反应温度为120℃、引发剂质量分数为4%、单体质量分数为14%、接枝反应时间为2.5h时,可得到接枝率为2.85%的PP-g-MAH。  相似文献   

9.
以马来酸酐(MAH)等为单体接枝聚丙烯作为聚丙烯(PP)/黏土复合材料熔融剂,考察了马来酸酐用量、引发剂过氧化苯甲酰(BPO)用量、反应时间、温度等因素对产物接枝率的影响,并通过红外光谱图对PP-g-MAH进行表征。结果表明,当m(PP):m(复配单体):m(BPO)=10.0:2.0:0.6、反应温度控制在120℃左右、复配单体为马来酸酐/苯乙烯时,熔融剂PP-g-MAH的接枝率可获得较大值3.9%。实验同时表明,反应时间对接枝率的影响不大;苯乙烯的加入对接枝率有较大的影响,与普通单体单一马来酸酐相比,加入苯乙烯的接枝率明显提高。  相似文献   

10.
以苯乙烯(S)、马来酸酐(M)、烯丙基磺酸钠(SA)为原料合成了三元共聚物防蜡剂SMSA。通过研究反应温度、反应浓度、反应物摩尔比、引发剂用量和反应时间五个因素对产物防蜡性能的影响,优化了合成反应条件。结果表明:单体摩尔比6∶6∶1,反应温度80℃,单体浓度40%,引发剂用量为单体量的2.0%,反应时间5 h,防蜡效果最好,酯化后的SMSAE兼具了高分子防蜡剂与表面活性剂防蜡剂的特点,防蜡率高达67.6%。  相似文献   

11.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

16.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

17.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

18.
Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

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