Fabrication of UV-Curing Linalool-Polysiloxane Hybrid Films with High Refractive Index and Transparency

In this article,a series of high refractive indices(1.50-1.53)thiol phenyl polysiloxane(TPS)were synthesized via hydrolytic sol-gel reaction.The Fourier transform infrared spectra(FT-IR)and nuclear magnetic resonance spectra(NMR)results showed that TPS conformed to the predicted structures.Natural terpene linalool was exploited as photocrosslinker to fabricate UV-curing linalool-polysiloxane hybrid films(LPH)with TPS via photoinitiated thiol-ene reaction.LPH rapidly cured under UV irradiation at the intensity of 80 mW/cm^(2) in 30 s,exhibiting good UV-curing properties.The optical transmittance of LPH in the wavelength of 300-800 nm was over 90%,exhibiting good optical transparency.The water contact angle and water vapor permeability results showed that the introduction of phenyl groups enhance the hydrophobicity and water vapor barrier properties of LPH.The results indicated the potential of LPHs in the applications of optical functional coatings.

Synthesis and Characterization of Sidechain Liquid Cryastaline Polysiloxanes Containting Either Cholesteryl or Cyanobiphenyl Mesogenic Groups

A series of side chain liquid crystalline polysiloxanes containing either cholesteryl or cyanobiphenyl mesogenic groups were synthesized by the hydrosilylation reaction of a polysiloxane containing Si H group with a vinyl terminated compound containing the mesogenic group. Their chemical structures were confirmed by IR, 1H NMR, and elemental analysis, Their phase behaviors were investigated by differential scanning calorimetry, optical polarizing microscope, and X ray diffraction techniques. The results show that all these polysiloxanes except PⅤ display smectic or nematic mesonorphism or both. The dependence of phase transition temperature on the rigidity of mesogenic unit. the length of spacer group, and the flexibility of Si(CH 3) 2O chain is also described.

SIDE CHAIN LIQUID CRYSTALLINE POLYSILOXANES CONTAINING CROWN ETHER AND BENZYL ETHER MOIETIES

Two kinds of side chain liquid crystalline polysiloxanes containing crown ether and benzyl ether were synthesized and characterized by optical polarization microscopy. Both the monomeric liquid crystals and polymeric liquid crystals show smectic phases.

Syntheses and Characterization of New Chiral Side-Chain Liquid Crystalline Polysiloxanes

A new serial chiral side-chain liquid crystal polysiloxanes containing L-Tyr structures were synthesized at room temperature. Both of them exhibited Sc phase at room temperature.

Silica-supported Polysiloxanes with Dithiacrown Ether Groups and Their Platinum Complexes

The present paper represents the syntheses of polypropyloxymethyldithia 15-crown-5 and 18-crown-6 supported on silica and their platinum complexes. The platinum complexes are effective catalysts for the hydrosilylation of olefins with triethoxysilane. The influences of temperature, amount of platinum complexes used and the nature of olefins used on the catalytic activity of the complexes are also investigated in this paper.

Two Side Chain β-CD Polysiloxanes Used as New Stationary Phase for Chiral Separation by HRGC

Two new stationary phases : (Ⅰ) [bikis(2,6-di-O-pentyl-3-O-hex-6O-pentyl-3-O-methyl)-β-CD-polysiloxane] and (Ⅱ) [heptkis(2,6-di-O-methyl-3-O-hex-6-enyl)-β-CD-polysiloxane] were synthesized and successfully used for GC separation of chiral isomers.The possess high column efficiency and exhibit fine chiral separation ability.

Synthesis of Multifunctional Polysiloxanes for Photorefractive Effect

A novel kind of multifunctional polysiloxane containing charge-transporting agent and as electro-optical chromophore has been prepared for photorefractive application. The structural characterization of this kind of polymer is presented by IR spectra and elemental analysis.

Mechanical and Thermal Properties of Polysiloxanes and NBR Blend Elastomer

A series of elastomers , based on NBR , polysiloxanes （PS） were prepared and characterized by tensile tests, thermogravimetry （ TG ） and differential scanning calorimetry （ DSC ）. Two kinds of vulcanizing agent, DMDBH （2,5-dimethyl- 2,5-di （ t- butyl perory ） hexane ） and DCP （ dicumylperoxide ） were used to investigate the influence of different vulcanizing agents on properties of PS/ NBR. The addition of PS to NBR was found to improve the thermal stability and decrease the tensile strength of NBR. The tensile strength decreased conshterably while the elongation at break increased obviously with the increase of PS content. The series using DMDBH as vulcanizing agent showed a higher tensile strength and elongation at break than the series using DCP as vulcanizing agent. Simultaneity the thermal stability increased with the increase of PS content.

SYNTHESIS AND CATALYTIC BEHAVIOR OF POLYSILOXANESUPPORTED FULLERENE PLATINUM OR RHODIUM COMPLEXES

Two polysiloxanes with pendant fullerene moieties and their platinum or rhodium complexes have been prepared from C-60 via amination with omega-decenylamine, followed by hydrosilylation with triethoxysilane and immobilization on fumed silica or by hydrosilylation with methyldichlorosilane and polycondensation with polydimethylsiloxanol, and then by reacting them with potassium chloroplatinite or rhodium chloride in acetone respectively under argon atmosphere. It was found that the four noble metal complexes are effective catalysts for the hydrosilylation of olefins with triethoxysilane. The regioselectivity of platinum complexes for styrene increases remarkably by introducing C-60 moiety. Factors influencing catalytic activity and the mechanism have been investigated.

SYNTHESIS AND PROPERTIES OF LIQUID CRYSTAL POLYSILOXANES WITH MESOGENIC STILBENE SIDE GROUPS

A variety of mesomorphic side-chain polysiloxanes were synthesized by using hydrosilylation reaction with dicyclopentadienylplatinum(II) (DPPC) as the catalyst. The mesogenic groups are derivatives of stilbene with cyano or nitro tail groups. The products were characterized by DSC, X-ray diffraction and polarizing optical microscopy (POM). All the polymers were found to have relatively low T-g and can form a smectic liquid crystal phase.

SYNTHESIS AND CHARACTERIZATION OF SIDE CHAIN LIQUID CRYSTATALLINE POLYSILOXANES CONTAINING BENZYL ETHER LINKING UNITS

Side chain liquid crystalline polysiloxanes containing benzyl ether linkingunits were synthesized by the hydrosilylation of poly (methylhydrosiloxane) with a series of4-(4-alkoxybenzyloxy)-4'-allyloxybiphenyl monomers [4-(4-methoxybenzyloxy )-4'-allyloxy-biphenyl(M_1), 4-(4-ethoxybenzyloxy)-4'-allyloxybiphenyl (M_2), 4-(4-propoxybenzyloxy)-4'-allyloxybiphenyl (M_3), 4-(4-butoxybenzyloxy)-4'-allylox(M_4), 4-(4-pentoxy-benzyloxy)-4'-allyloxybiphenyl (M_5), 4-benzyloxy-4'-allyloxybiphenyl (M_6)]. The phasebehavior of monomeric and polymeric liquid crystals was characterized by differential scan-ning calorimetry and optical polarization microscopy where the groups are ranged frommethoxy to pentoxy Both the monomeric and polymeric liquid crystals exhibit 1iquidcrystal behaviors.

SYNTHESIS AND CHARACTERIZATION OF PALLADIUM COORDINATING IMINE SIDE CHAIN LIQUID CRYSTALLINE POLYSILOXANES

New thermotropic chloro-bridged dinuclear palladium coordinating imine side chain liquid crystalline polysiloxanes have been synthesized. Their mesomorphic properties have been investigated by DSC, X-ray diffraction and polarizing microscopy. The polymeric complexes show nematicdiscotic (Nd) mesophase. It is found that the temperature range of liquid crystalline state of chloro- bridged polymeric complexes is much wider than that of acetato- bridged ones and imine side chain polysiloxane. This indicates that the disc-like chloro-bridged palladium complexing units play a role as mesogen in mesophase.

Oxidation, Chain Scission and Cross-Linking Studies of Polysiloxanes upon Ageings

The comparison between physical properties and chemical structures of several polysiloxanes was studied at initial state and upon ageings. Techniques such as densimetry, gel permeation chromatography, FTIR spectroscopy, thermogravim- etric analysis coupled with IR spectroscopy and the new tool photo-DSC were used to give assessments of average mo- lecular weight, chemical evolution, cristallinity and thermal stability. Different types of ageing such as thermal ageing (60?C and 100?C), photo-ageing and acid vapour ageing were performed. After ageing we observed an evolution of chemical structures and physical properties for all samples. The main pathway of degradation is given for each sample. It results in oxidation, chain scission or cross-linking. Cross-linking levels are dependant on the type of ageing, the chemical structure and the initial rate of cristallinity. Cross-linking reactions are favoured after photo-ageing. Oxidation is higher for polysiloxane with aliphatic carbon chain.

SYNTHESIS AND CHARACTERIZATION OF β-DIKETONE BASED SIDE CHAIN LIQUID CRYSTALLINE POLYSILOXANES

A new type of β-diketone based side chain liquid crystalline polysiloxanes (DKLCP) with different length of flexible spacers and end groups have been synthesized by hydrosilation reaction. This is liquid crystal polymers (LCP) using coordinating β-diketone ligand as mesogens. The phase behaviour of DKLCP polymers was studied by differential scanning calorimetry and polarizing microscopy. X-ray diffraction investigations demonstrated that the polysiloxanes with sufficiently long flexible spacers were smectic liquid crystal polymers, while those with much shorter spacers were nematic ones.

新型纳米杂化长链烷基/氨基共改性倍半硅氧烷防水剂的合成与性能研究

随着欧盟环保要求对PFOA、PFOS、APEO等含氟化合物的严格限制,无氟防水剂成为织物整理剂的主流.基于此,本研究将端环氧聚二甲基硅氧烷(α,ω-ESO)与N-β-(氨乙基)-γ-氨丙基甲基二甲氧基硅烷(KH-602)先氨解开环合成硅氧烷基封端的聚硅氧烷反应性中间体(AESO),再将其与正硅酸乙酯(TEOS)及辛基三乙氧基硅烷(OTES)进行水解缩聚,合成了一种新型纳米杂化长链烷基/氨基共改性倍半硅氧烷树脂,并以其制备得到防水剂RAPS@SiO_(2).以棉织物布样作为应用对象,用FT-IR、XRD、SEM、接触角测量仪等仪器对其进行表征测试.结果表明:与空白织物相比,采用3%浓度RAPS@SiO_(2)防水剂经一浸一轧工艺处理后的棉织物在保持原有光泽的同时,在防水性、柔软度等方面有明显提升,水接触角WCA=151.7°,滚动角SA=9.2°,静态吸水时间达到195 min,并且改性织物经过5次循环水洗、100次磨损后,仍然具有良好的疏水性能.无氟防水剂RAPS@SiO_(2)的开发为制备环境友好型超疏水织物防水剂提供新思路.

脉冲磁场幅值对制备聚硅氧烷复合材料的电磁屏蔽性能影响规律

脉冲磁场已被证实通过诱导纳米粒子在基体中取向排列可以显著提高复合材料的电磁屏蔽性能,然而脉冲磁场幅值对复合材料电磁屏蔽性能的影响规律尚不明确。因此,采用脉宽为10μs、频率为50Hz的脉冲磁场诱导片状羰基铁(flaky carbonyl iron,FCI)在聚二甲基硅氧烷(polydimethylsiloxane,PDMS)中定向排列,研究磁场幅值(0~0.7T)对复合材料电磁屏蔽性能的影响规律。用扫描电子显微镜(scanning electron microscope,SEM)和X射线衍射(X-ray diffraction,XRD)对纳米粒子的取向和排列进行了表征。结果表明,脉冲磁场可以有效控制羰基铁的取向和排列,形成导电网络结构,提高复合材料的导电性,最终显著提高取向复合材料的电磁屏蔽性能。脉冲磁场对复合材料的屏蔽效能增强效果可达27%,达到的最高屏蔽效率为15.36dB。理论分析和实验结果的一致性证实了微秒级脉冲磁场在改善复合材料电磁屏蔽性能方面的有效性。该研究制备的高性能柔性电磁屏蔽复合材料具有应用于先进电子设备的潜力。

改性石墨烯纳米带/双马来酰亚胺复合材料的摩擦学性能

为了改善石墨烯与双马来酰亚胺(BMI)树脂的相容性,并使其在摩擦过程中快速形成高质量自润滑转移膜,用超支化聚硅氧烷(HBPSi)和Ni纳米粒子共同改性石墨烯纳米带(GNRs),制备了HBPSi/Ni/GNRs复合粒子,将其引入到BMI树脂中制备出HBPSi/Ni/GNRs/BMI复合材料。采用FTIR、SEM、TEM、摩擦磨损试验机及分子动力学模拟对复合粒子的结构、形貌及添加量和复合材料的摩擦学性能的影响进行了考察,并探究了其摩擦磨损机理。结果表明,HBPSi和Ni纳米粒子成功负载到GNRs表面上。与GNRs相比,HBPSi/Ni/GNRs复合粒子能够显著提升BMI复合材料的摩擦学性能。当HBPSi/Ni/GNRs复合粒子添加量(质量分数)为0.6%时,HBPSi/Ni/GNRs/BMI复合材料的摩擦系数和体积磨损率均降至最低,分别为0.18和1.9×10^(-6)mm^(3)/(N·m)。HBPSi/Ni/GNRs复合粒子与BMI树脂强的界面作用是导致其复合材料抗剪切能力提升的关键。

刚性基团桥接聚硅氧烷/乙基纤维素混合膜的制备及其CO_(2)的分离

以3种含刚性基团(六氟酰亚胺、萘基酰亚胺和芴)桥接聚硅氧烷(6FBPMS、NTBPMS和BAFBPMS)为改性剂,乙基纤维素(EC)为基质,通过溶液共混、涂敷法制备了3类不同负载量桥接聚硅氧烷的改性EC混合膜(6FBPMS/EC、NTBPMS/EC和BAFBPMS/EC)。3类复合膜具有良好的成膜性,且显示出高的力学性能和热稳定性。测试了混合膜对体积比都为1∶1的混合气体对CO_(2)/N_(2)和CO_(2)/CH4的透过选择性。结果表明,相较于纯EC膜,3类膜在保持选择性的同时,显示出更高的CO_(2)透过性;特别是NTBPMS/EC混合膜,其对CO_(2)透过性达到213 barrer以上,是纯EC的4.9倍。

超支化聚硅氧烷在改性BMI/CE树脂方面的研究进展

综述了近年来超支化聚硅氧烷改性双马来酰亚胺和氰酸酯树脂的研究进展,重点总结了超支化聚硅氧烷在改性树脂力学性能、热性能及阻燃性能方面的应用,并对超支化有机硅功能高分子未来的发展作出了展望。

含聚硅氧烷链段邻苯二甲腈树脂的制备及性能

以端羟基聚二甲基硅氧烷和4-硝基邻苯二甲腈为原料,在强极性溶剂中进行亲核取代反应合成了含聚硅氧烷链段邻苯二甲腈树脂(SIPH),并利用氨基改性剂(AWL)与该树脂进行反应制备了改性含聚硅氧烷链段邻苯二甲腈树脂预聚物(SIPH-AL)。通过红外光谱和核磁共振表征了SIPH树脂的化学结构;采用差示扫描量热法、红外光谱法、热重分析和动态力学热分析表征了SIPH-AL的固化行为和固化物的耐热性。结果表明,SIPH-AL起始固化温度为207℃,其固化物在空气和氮气中失重5%的温度(T_(d5))及1000℃质量保留率分别是453℃,29%和500℃,77%;石英纤维增强SIPH-AL复合材料室温和600℃时的弯曲强度分别为515.5 MPa和94.5 MPa,玻璃化转变温度(T_(g))高于500℃。