阴离子本体开环聚合反应挤出合成聚三氟丙基甲基硅氧烷

以同向紧啮合双螺杆挤出机为反应器,硅醇钠/乙酸乙酯(EA)为引发体系,通过三氟丙基甲基环三硅氧烷(F3)阴离子本体开环聚合,制备了聚三氟丙基甲基硅氧烷(PMTFPS)。采用红外光谱(FT-IR),核磁共振(1H-NMR)和凝胶渗透色谱(GPC)确认了聚合物的结构与分子量,用电离飞行时间质谱分析了副产物的组成。研究表明,提高反应温度和EA用量可使反应平衡点提前到达。而螺杆转速对反应的主要影响在于改变聚合反应时间。因此,控制适当反应条件,使反应在平衡点到来时间之前终止,可得到高分子量以及高收率的PMTFPS。所得产物的数均分子量为2.41×105,分子量分散指数为1.12,产率为90.5%。     

有机硅耐热涂料的研究

本课题借助现代化分析手段对有机硅、甲基有机硅及环氧改性有机硅树脂的固化过程进行了研究,以此为依据制定了合理的固化工艺;通过比较不同配方色漆的性能,确定了以TiO2为颜料,SiO2、云母粉、滑石粉石粉为填料的色漆组成。该涂层具有优异的耐热性和机械性能,综合性能良好,长期耐热温度大于250℃,短期耐热大于550℃,可作为耐高温涂料。     

All‐Polymer Solar Cells Based on a Conjugated Polymer Containing Siloxane‐Functionalized Side Chains with Efficiency over 10%

A novel wide‐bandgap conjugated copolymer based on an imide‐functionalized benzotriazole building block containing a siloxane‐terminated side‐chain is developed. This copolymer is successfully used to fabricate highly efficient all‐polymer solar cells (all‐PSCs) processed at room temperature with the green‐solvent 2‐methyl‐tetrahydrofuran. When paired with a naphthalene diimide‐based polymer electron‐acceptor, the all‐PSC exhibits a maximum power conversion efficiency (PCE) of 10.1%, which is the highest value so far reported for an all‐PSC. Of particular interest is that the PCE remains 9.4% after thermal annealing at 80 °C for 24 h. The resulting high efficiency is attributed to a combination of high and balanced bulky charge carrier mobility, favorable face‐on orientation, and high crystallinity. These observations indicate that the resulting copolymer can be a promising candidate toward high‐performance all‐PSCs for practical applications.     

氟化硅氧烷改性环氧树脂的制备与性能

首先,以全氟(2-甲基-3-氧杂己基)氟化物(六氟环氧丙烷二聚体)和N-(β-氨乙基)-γ-氨丙基三甲氧基硅烷(KH792)为原料制备一种氟化硅氧烷,用FTIR和1HNMR表征其结构.然后,将氟化硅氧烷与聚醚胺共同固化环氧树脂DGEBA(双酚A型二缩水甘油醚),测试了改性环氧树脂复合材料的性能.结果表明,与未改性环氧树...     

具有核壳相反转特性的丙烯酸酯/硅氧烷共聚乳液的合成

以丙烯酸丁酯，甲基丙烯酸甲酯，八甲基环四硅氧烷和适量γ－甲基丙烯酰氧丙基三甲氧基硅烷为原料，以过硫酸铵和十二烷基苯磺酸为复合引发催化剂，采用一步乳液聚合法（即自由基共聚与缩聚反应同步进行），制成了涂料用，具有核壳结构的丙烯酸酯（核）／硅氧烷（壳）共聚乳液，考察了聚合温度，硅氧烷用量，乳化剂种类，乳液放置时间对共聚物乳胶粒形态及其粒径的影响，结果表明，乳液放置一定时间后，乳胶粒结构发生相反转，最终变成以聚硅氧烷为核，聚丙烯酯酯为壳的热力学稳定结构。     

The effect of the mass ratio of hard and soft segments on some properties of thermoplastic poly(ester‐siloxane)s

A series of thermoplastic elastomers based on soft polydimethylsiloxane (PDMS) and hard poly(butylene terephthalate) (PBT) segments was synthesized using a two‐step transesterification reaction in the melt. The molar mass of the soft PDMS component was constant (M?_nPDMS = 1056 g mol^?1) while the starting reaction mixture compositions were varied to obtained copolymers with a mass ratio of hard to soft segments in the range from 70/30 to 40/60. The structure and composition of the copolymers was verified by ¹H NMR spectroscopy. It appeared that there was a pronounced molar mass maximum when the PBT content of the copolymers was approximately 60 mass%, whereas all samples were considerably inhomogeneous with respect to the distribution of the lengths of the hard segments. Differential scanning calorimetry (DSC) thermograms showed that the melting and crystallization temperature increased with increasing PBT content, as did the total degree of crystallinity, which was confirmed by wide‐angle X‐ray scattering (WAXS) analysis. Thermogravimetric analysis (TGA) performed in nitrogen gave subtle differences for samples of different composition, including that of the PBT homopolymer, whereas in oxygen these differences were more pronounced in the way the thermo‐oxidative stability of the obtained copolymers decreased with decreasing PBT content. Finally, it was shown that the hardness depended directly on the PBT content, ie the higher the PBT content, the greater the hardness of the corresponding copolymer. Copyright © 2004 Society of Chemical Industry     

含氢聚甲基硅氧烷/聚丙烯酸酯复合乳液研究 Ⅰ.复合乳液的制备及其性能

合成了含氢聚甲基硅氧烷／聚（丙烯酸丁酯－羟甲基丙烯酰胺）复合聚合物乳液。探讨了引发剂用量、反应温度、聚合方法、含氢聚甲基硅氧烷及羟甲基丙烯酰胺含量对聚合反应转化率，聚合及存放稳定性的影响。考察了复合乳液的成膜性及胶膜性质。柔软性能测试表明，所制备的复合乳液可作为织物柔软剂使用。     

Modification of the properties of some polyblends and reinforced polymers

In the present paper we shall deal with: (a) Polyblends made of a polyurethane (PU) based on a polyether and diphenyl-methane-diisocyanate and an acrylic terpolymer (AT) system and, (b) glass fibre reinforced poly-(organosiloxane), (SR). We now report some differential scanning calorimetry (d.s.c.) measurements and the effect of thermal cycling exposure on these polymers. Stress-strain tests were done on an Instron universal testing machine. The modification of the properties on the polymers after blending and reinforcing respectively are discussed. At certain ratio PU to AT the behaviour of the polyblend to thermal cycling exposure is better than that of PU. The presence of the reinforcing agent in the silicone polymer significantly improves its mechanical and thermal properties.     

聚醚型硅油改性水性聚氨酯的制备与性能研究

以异佛尔酮二异氰酸酯、聚四氢呋喃醚二醇、二羟甲基丙酸、聚醚型硅油等为原料制备了硅改性水性聚氨酯(PUDS)。采用红外光谱、透射电镜等对PUDS乳液及其涂膜进行了结构表征和性能测试,结果表明:有机硅有效地接枝在水性聚氨酯分子链上,涂膜耐水性显著提高,乳液稳定性良好,随着聚醚型硅油用量的增加,涂膜拉伸性能呈微弱下降趋势,当硅油用量为2%时,拉伸强度为16.7 MPa,断裂伸长率为753.7%,断裂强度15.8 MPa,综合性能优良。     

正交实验优选HTBN/聚氨酯合成的最佳工艺条件

以端羟基聚丁二烯-丙烯腈(HTBN)为软段、甲苯二异氰酸酯(TDI)为硬段和端氨基硅油为改性剂,合成了端氨基硅油改性HTBN型聚氨酯(PU)。以n(-NCO)∶n(HTBN)、n(硅油)∶n(HTBN)、n(扩链剂)∶n(HTBN)和硅油加入方式为主要影响因素,并以断裂伸长率、邵氏硬度、拉伸强度和定伸应力为考核指标,采用L9(34)正交实验方法优选该PU合成的最佳工艺条件。研究结果表明,当n(-NCO)∶n(HTBN)=1.6∶1、n(硅油)∶n(HTBN)=6∶100、n(扩链剂)∶n(HTBN)=5∶100且在后期加入端氨基硅油时,端氨基硅油改性HTBN型PU的综合性能最好。