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1.
无皂乳液聚合制备增稠剂及其性能研究   总被引:3,自引:0,他引:3  
以聚乙烯醇为胶体保护剂、N,N′-亚甲基双丙烯酰胺为交联剂,用过硫酸钾-亚硫酸钠引发丙烯酸、丙烯酰胺、丙烯酸丁酯进行无皂乳液聚合,以制备高性能的涂料印花增稠剂,所得产品稳定性好、增稠效果优良。并研究了交联剂、引发剂、胶体保护剂的用量等聚合条件对增稠剂性能的影响。引发剂用量增加,增稠剂黏度下降,黏度指数上升。交联剂用量增加可使增稠剂的黏度出现极大值,但黏度保留率下降。采用PVA作为胶体保护剂,产品增稠能力强,稳定性好,耐电解质等综合性能均较好。  相似文献   

2.
阳离子型涂料印花用增稠剂的制备及其性能研究   总被引:1,自引:0,他引:1  
采用反相乳液聚合的方法,以N,N'-亚甲基双丙烯酰胺为交联剂,过氧化氢异丙苯-亚硫酸氢钠为氧化-还原引发剂,对丙烯酰胺(AM)、阳离子单体甲基丙烯酰胺丙基三甲基氯化铵(MAPTAC)进行共聚反应,制备了一种增稠性能好,耐盐性能高,使用方便的阳离子型印花涂料用增稠剂.通过正交实验和极差分析确定了影响增稠性的显著性因素.通过单因素实验确定了最佳反应条件.结果表明:含增稠剂3%白浆的表观黏度可达47 Pa·s,0.05%的氯化钠水溶液巾的黏度保留率为32.9%,黏度指数为23.6%,使用时白浆达到最大黏度时间为1 min.  相似文献   

3.
以丙烯酸为原料,季戊四醇三烯丙基醚为交联剂,水为溶剂,在引发剂作用下采用乳液聚合法得到聚丙烯酸增稠剂。研究了温度、交联剂用量、引发剂用量等对聚丙烯酸增稠剂性能的影响,通过正交试验找出最佳实验方案,并对聚丙烯酸增稠剂进行傅里叶变换红外光谱以及热重分析表征。结果表明,制备的聚丙烯酸增稠剂在日化应用中具有优异增稠性能以及良好的分子链热稳定性。  相似文献   

4.
用反相乳液聚合方法制备了增稠性好的聚丙烯酸乳胶。研究了引发剂、交联剂、单体浓度、水相pH、聚合温度和油-水相重量比对聚丙烯酸乳胶增稠性影响。试验结果表明,通过控制水相pH和引入非离了型亲水单体(如丙烯酰胺)可制得耐电解质性能好的聚丙烯酸增稠剂。  相似文献   

5.
聚丙烯酸铵增稠剂的制备工艺   总被引:2,自引:0,他引:2  
孙磊  曾小君 《化工时刊》2002,16(9):41-45
介绍了以丙烯酸、氨水、煤油、N,N-亚甲基双丙烯酰胺、过硫酸钾、乳化剂等为原料制备聚丙烯酸铵增稠剂的工艺。讨论了氨水用量、中和反应时间、聚合反应温度、煤油用量、交联剂用量、引发剂用量等因素对聚丙烯酸铵增稠剂产品吸水性和增稠性能的影响。实验结果发现,当丙烯酸58g、氨水50g、中和反应时间2h、煤油40.8g、N,N-亚甲基双丙烯酰胺0.133g、相对分子质量调节剂(适量),过硫酸钾0.266g、乳化剂6g、聚合反应温度为65℃、聚合反应时间2h,得到的产品吸水量大,增稠性能良好,粘度≥2200mPa.s。  相似文献   

6.
郭玉杰 《山东化工》2011,40(3):28-31
以α-甲基丙烯酸和多种丙烯酸酯类为原料,过硫酸钾(KPS)为引发剂,十二烷基硫酸钠和吐温-60为复配乳化体系,邻苯二甲酸二烯丙酯为交联剂,通过乳液聚合,合成出增稠剂。研究了甲基丙烯酸十八烷基酯(SMA)含量、交联剂用量、引发剂用量等因素对共聚物增稠剂增稠性能的影响。结果显示,单体配比是影响增稠剂各项性能的最主要因素,当SMA=1%时。增稠性能最好;随着交联剂的增加,耐盐性下降,增稠黏度先增大后减小,在交联剂为0.3%时出现最大值;引发剂量为0.3%时,所得聚合物的增稠性能最好,为0.4%时,所得聚合物的耐盐性最好。  相似文献   

7.
反相乳液聚合制备耐盐两性增稠剂   总被引:1,自引:0,他引:1  
以司班-60、TX-10为复配乳化体系,N,N-亚甲基双丙烯酰胺为交联剂,用过硫酸钾引发丙烯酸钠和甲基丙烯酰氧乙基三甲基氯化铵(DMC)进行反相乳液聚合,制备高耐盐的涂料印花增稠剂.实验探讨了引发聚合的最佳引发剂、交联剂用量以及所得产品的耐盐性、流变性和耐稀释性.结果表明,当引发剂、交联剂占单体量0.3%,阳离子含量占单体量4.5%时,其综合增稠效果最佳.  相似文献   

8.
通过二异氰酸酯和聚乙二醇在封端剂的存在下合成了一种水性聚氨酯缔合型增稠剂,考察了不同的单体、链封端剂以及反应的工艺条件对产物增稠性能的影响,并讨论了增稠剂相对分子质量和相对分子质量分布与其增稠性能之间的关系.  相似文献   

9.
利用异佛尔酮二异氰酸酯(IPDI)与聚乙二醇(PEG-6000)反应制备预聚体,以丙三醇和三羟甲基丙烷作为扩链剂,十六醇为封端剂,制备了星型结构的水性聚氨酯缔合型增稠剂(SHEUR)。采用FTIR和GPC对SHEUR分子结构进行了表征;利用黏度计和旋转流变仪对SHEUR水溶液的黏度、SHEUR对乳液增稠后的黏度以及SHEUR水溶液的流变性进行了分析,并与合成的线型结构水性聚氨酯缔合型增稠剂(LHEUR)进行对比,考察了不同结构的增稠剂分子对其增稠性能的影响。结果表明:SHEUR增稠效果比LHEUR好;向丙烯酸乳液中加入增稠剂的质量分数为1%时,以三羟甲基丙烷为扩链剂的SHEUR-a增稠后的黏度为61 440 m Pa·s,而以1,6-己二醇为扩链剂的LHEUR-b增稠后黏度仅为202 m Pa·s;低剪切时,SHEUR黏度维持在较高水平,剪切速率大于100 s-1后,SHEUR出现剪切变稀现象。对SHEUR流变性和乳液增稠后粒径的测定结果表明,所合成的SHEUR具有良好的触变性。  相似文献   

10.
以多种丙烯酸酯单体通过乳液聚合方法制备了一种聚丙烯酸酯乳液增稠剂。简介了其合成工艺 ;讨论了引发剂、交联剂、单体、乳化剂以及反应温度、时间和加料速度等因素对乳液稳定性及增稠性能的影响。同时对该乳液的应用也做了简要介绍  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   

12.
It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.  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   

18.
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   

19.
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   

20.
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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