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1.
高固体分丙烯酸树脂相对分子质量的研究   总被引:1,自引:0,他引:1  
采用溶液聚合法合成高固体分丙烯酸树脂,用凝胶渗透色谱(GPC)法分析引发剂的种类和用量、反应温度及聚合工艺对丙烯酸树脂的相对分子质量及其分布的影响。结果表明,选用偶氮二异丁腈和过氧化苯甲酰两种引发剂进行复配可提高聚合物的相对分子质量;采用“饥饿态”聚合工艺进行聚合反应可有效控制聚合物的相对分子质量,且相对分子质量分布均匀,分散度小于2;当引发剂用量为2%,在110℃的反应条件下制得的丙烯酸树脂的综合性能优异,固含量超过70%,相对分子质量可达4万。  相似文献   

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从溶剂型丙烯酸树脂的分子结构和施工性能等方面分析了不同类型丙烯酸树脂相对分子质量分布的影响,并介绍了相对分子质量分布的控制理论和对不同相对分子质量分布的丙烯酸树脂聚合的控制方法。  相似文献   

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采用种子乳液法制备了核壳型聚丙烯酸酯(ACR),并分别采用十二烷基硫醇和正辛基硫醇作为链转移剂对 ACR壳层的聚甲基丙烯酸甲酯(PMMA)进行相对分子质量调节,并用于PVC共混改性。黏度法对PMMA的相对分子质量测定表明,正辛基硫醇的相对分子质量调节能力较强。采用差示扫描量热分析测定PMMA的玻璃化转变温度(Tg),并对共混树脂进行动态力学性能测试。当ACR壳层PMMA平均相对分子质量低于12×104时,PVC/ACR 共混树脂的缺口冲击强度大大提高。与纯PVC相比,共混树脂的Tg均略有提高,其增量随ACR壳层PMMA平均相对分子质量的降低而减小。动态力学性能测试结果表明,ACR壳层聚合物平均相对分子质量越低,共混物分子链段运动活化能提高越少。  相似文献   

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塑料用涂料     
<正>201410019具有金属质感且耐水性优异的汽车内饰塑料件及其涂装方法:JP2013-215 887[日本专利公开]/日本:Nippon Bee Chemical Co.,Ltd.(Kanemura,Satoshi等).-2013.10.24.-16页.-2012/85 545(2012.08.04);IPC B32827/20题述塑料件由透明塑料基材和背涂层及屏蔽层构成。其中,(a)背涂层由一种组合物(含有树脂和非浮型沉积铝颜料)经涂覆而制得;(b)屏蔽层由一种清漆组合物(含有玻璃化转变温度在30~120℃、质均相对分子质量为40 000~200 000的丙烯酸树脂)经涂覆而制得。  相似文献   

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水性丙烯酸改性环氧树脂性能的影响因素研究   总被引:1,自引:0,他引:1  
刘敏  宋洋  朱华  汪的华  甘复兴 《上海涂料》2010,48(11):13-17
采用二步酯化工艺,制得不同相对分子质量及不同丙烯酸用量的水性丙烯酸改性环氧树脂。研究了数均相对分子质量、羧基含量对改性树脂性能的影响,为涂料性能的进一步优化与改善提供了依据。  相似文献   

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用凝胶渗透色谱测定了不同批号的薄膜专用聚丙烯(PP)树脂T38F的相对分子质量及其分布,评价了产品的相对分子质量及其分布对加工性能的影响.测定结果的重复性和再现性良好.根据分析结果调整相关工艺条件后生产的PP T38F能够满足用户的加工要求.实验结果表明:薄膜专用PP树脂的重均分子量(Mw)控制在(25.0~29.0)...  相似文献   

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以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(n-BA)、丙烯酸(AA)、甲基丙烯酸羟乙酯(HEMA)、苯乙烯(St)和4-叔丁基环己丙烯酸酯(TBCH)为聚合单体,巯基乙醇(β-ME)为链转移剂,偶氮二异丁腈(AIBN)为引发剂,醋酸丁酯(BAC)为溶剂,采用溶液聚合法合成了一系列低相对分子质量的羟基丙烯酸树脂。以氨基树脂作为固化剂,研究了丙烯酸树脂的羟值、酸值及玻璃化转变温度对制成的氨基烤漆漆膜的摆杆硬度、光泽、耐水性、耐酸性及耐碱性的影响。结果表明,当树脂的羟值(以KOH计)为147 mg/g,酸值(以KOH计)为21 mg/g,玻璃化转变温度为25°C时,所制漆膜的综合性能最佳。  相似文献   

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采用4-甲基苯酚、3-甲基苯酚与甲醛,经两步法反应制备了一系列正性光致抗蚀剂用酚醛树脂。制备的酚醛树脂的重均相对分子质量及相对分子质量分布分别在(5~17)×10~3和2.75~11.67范围内。探讨了甲醛用量、反应时间、催化剂用量、水选对相对分子质量及相对分子质量分布的影响。增加甲醛和催化剂用量将使相对分子质量增大、相对分子质量分布变宽。延长反应时间也将使相对分子质量分布变宽。但增加水洗次数将使相对分子质量减小、相对分子质量分布变窄。结果表明,通过改变反应条件可有效地控制酚醛树脂的相对分子质量及相对分子质量分布。  相似文献   

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以间苯二甲酸-5-磺酸钠(5-SSIPA)与新戊二醇缩聚,制备亲水性中间体.用该中间体与羟基丙烯酸树脂、新戊二醇、三羟甲基丙烷和己二酸进一步缩聚,制得聚酯丙烯酸杂化树脂,加水分散后得其水分散体.研究了反应温度、羟基丙烯酸树脂的玻璃化温度及含量对杂化多元醇水分散体及其相应涂膜性能的影响.结果发现,适宜的杂化反应温度为22...  相似文献   

10.
反式 -1,4-聚异戊二烯相对分子质量的调节   总被引:6,自引:3,他引:6  
采用负载钛本体沉淀聚合法,以氢气作链转移剂,制备了不同相对分子质量的反式-1,4-聚异戊二烯(TPI),讨论了老化、氢气调节及塑炼对其相对分子质量的影响,以及不同相对分子质量TPI的结构与性能。结果表明,本体系合成TPI的数均相对分子质量为(5~15)×104,相对分子质量分布为2.00~3.00;门尼粘度为20~120时,随着TPI相对分子质量的降低,其结晶速度提高,结晶度无明显变化,拉伸强度明显降低,扯断伸长率、屈服强度和邵尔A型硬度无明显变化。  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   

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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   

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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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