Synthesis and properties of prepolymers and their siloxane analogues by thiol‐ene polyaddition of limonene with dithiols

This work presents a synthesis of monomers from a natural compound (limonene) and dimethylsiloxanes with various chain lengths by hydrosilylation. Based on these monomers, prepolymers with various lengths of the siloxane and methylene parts, as well as their analogues without siloxane moieties, were obtained by thiol‐ene polyaddition with ethanedithiol, butanedithiol and hexanedithiol. Their physicochemical characteristics, namely the thermal stability, phase behaviour and intrinsic viscosity of the polymers obtained, were compared as a function of the length of the methylene spacer and the siloxane part in the polymer chain. © 2019 Society of Chemical Industry     

硅量子点的表面改性技术

硅量子点具有新颖的光电性能,有望在光电、光伏和生物标记等领域发挥重要作用.为了使硅量子点表现出优异而稳定的光电性能,能够有效地被应用,通常需要对硅量子点的表面进行改性.针对表面起初被氢或氯钝化的硅量子点,详细地介绍了最近国内外在硅量子点表面改性方面的研究进展,重点介绍了表面改性技术对硅量子点的分散和发光等性能的影响,分析讨论了最具代表性的表面改性技术——氢化硅烷化的机理以及其对硅量子点性能的影响,提出了今后发展硅量子点表面改性技术的方向和应该注意的问题.     

聚醚改性有机硅表面活性剂的合成与性能

以含氢硅油与端烯丙基聚醚为原料,在氯铂酸的催化作用下,经硅氢加成反应合成了聚醚改性有机硅乳化剂。通过正交实验测定反应的转化率,探讨了反应时间、反应物比例、催化剂用量以及反应温度对反应的影响,并得出较适宜的反应条件为：反应时间为7h,n（Si—H）：n（C=C）--1：1,催化剂用量为20μg/g,反应温度为130℃,在该条件下,含氢硅油中Si—H的转化率达96％。由此制备的表面活性剂能有效降低表面张力,具有优良的乳化性能。初步讨论了含氢硅油与聚醚反应生成的共聚物的阴离子化反应,合成了硫酸盐型阴离子表面活性剂,由于结构的差异,产物HLB值有所增加。     

UV curing of epoxy functional hybrid silicones

Several epoxy difunctional hybrid alkylene‐silicone telomers with different silicone characters and organic spacers (linkers) were prepared via the platinum‐catalyzed polyhydrosilylation of α,ω‐dihydrosiloxanes and α,ω‐dienes. Thereafter, the resulting Si? H‐terminated prepolymers were terminally functionalized with 4‐vinyl‐1,2‐epoxycyclohexane or allyl glycidyl ether. In the presence of a lipophilic cationic photoinitiator, the terminally epoxy‐functionalized hybrid alkylene–silicone telomers were photopolymerized to give crosslinked, soft, elastomeric, and transparent films. The progress of the photoinitiated cationic ring‐opening epoxide polymerizations was monitored using optical pyrometry. Potential applications for these novel photocurable epoxy‐functional telomers are as modifiers for UV curable coatings, printing inks, adhesives, and release coatings. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

丙烯酸十八酯改性硅油的合成研究

以含氢硅油和丙烯酸十八酯为原料、氯铂酸为催化剂,通过硅氢加成反应合成了丙烯酸十八酯改性硅油。研究了催化剂用量、反应温度、反应时间和物料比等因素对反应的影响。通过正交实验和对相关因素的研究确定出反应的最佳条件:温度75℃,n(CC)∶n(Si—H)=1.1∶1,铂用量为反应物质量的0.008%,反应时间4 h,溶剂用量是反应物质量的30%;由红外表征证实,产物接枝上了丙烯酸十八酯。     

Iron‐Catalyzed Hydrosilylation of Esters

The first hydrosilylation of esters catalyzed by a well defined iron complex has been developed. Esters are converted to the corresponding alcohols at 100 °C, under solvent‐free conditions and visible light activation.     

硅胶负载铂催化剂催化合成二环戊基二氯硅烷

以二氯硅烷(DCS)和环戊烯为原料,在硅胶负载铂催化剂的催化作用下,经硅氢加成催化合成二环戊基二氯硅烷(DCPCS)。采用红外光谱和色质联机等手段表征了产物结构。考察了原料配比、催化剂的用量、催化剂的重复使用性能、反应温度、反应时间等因素对产物收率的影响。结果表明,合成DCPCS的最佳工艺条件为:二氯硅烷用量1.0 mol,n(DCS):n(环戊烯)=1.0,催化剂用量1.2 g,反应压力1.2 MPa,反应温度120℃,反应时间6 h,DCPCS的收率达88.6%,产物质量分数为99.1%。     

高档香波调理剂--聚硅氧烷的合成与应用

含氢的聚硅氧烷与烯丙醇、聚氧乙烯烯丙醚进行硅氢化反应,再与氯乙酸进行酯化反应,最后通过季胺化反应与叔胺、水制得香波用聚硅氧烷季铵盐,其转化率分别达到了９８％、９０％和９５％。洗发香波中的最佳用量为３％～５％。     

羧基硅油亚麻柔软剂的制备与表征

以甲基丙烯酸甲酯(MMA)、聚甲基氢硅氧烷(PMHS)为单体,在H2PtCl6催化作用下进行硅氢加成反应,合成羧基改性硅油(PMHS-g-MMA)并用作亚麻织物柔软剂.利用IR和1H-NMR对聚合物的结构进行表征分析,结果表明获得了预想产物(MMA与PMHS发生了接枝反应,接枝产物主要是β-1,2加成产物,α-1,2加成和1,4-加成接枝产物的量很少).     

Highly Efficient and Chemoselective Ruthenium‐Catalyzed Hydrosilylation of Aldehydes

The highly chemoselective hydrosilylation of aldehydes was achieved using a ruthenium catalyst activated by a household fluorescent light (30 W) at or below room temperature. The hydrosilylation was almost exclusive to aldehydes over ketones and olefins.