聚硅氧烷-聚丙烯酸酯-聚氨酯三元复合乳液的制备与表征及其胶膜性能

用异佛尔酮二异氰酸酯与仲羟基封端的聚硅氧烷(PMTS)反应在聚硅氧烷分子链端引入异氰酸酯基团, 然后将其与聚丙二醇、二羟甲基丙酸等反应制备聚硅氧烷改性聚氨酯(PSU)预聚体, 再以甲基丙烯酸甘油酯(GM)为偶联剂在PSU链上引入双键, 最后加入丙烯酸酯单体和交联剂乳化后通过乳液聚合制备了偶联型聚硅氧烷聚丙烯酸酯改性聚氨酯(PSU-X-AC)三元复合乳液. 同样条件下不使用偶联剂制备了非偶联型三元复合乳液(PSU-AC). 无论是否使用偶联剂, 三元复合乳液的稳定性都明显优于不含PAC的PSU二元乳液. 对于三元复合乳液及其胶膜的性能表征结果显示, 与非偶联型PSU-AC三元乳液相比, 偶联型PSU-X-AC乳液的乳胶粒尺寸较小, 粒径分布更均一|偶联型三元乳液的表面张力较小|其胶膜的力学强度远优于非偶联型|除非在PMTS分子量较高的情况下, 偶联型乳胶膜中未观察到非偶联型所见的相分离, 偶联剂GM的使用对提高材料的憎水及力学性能有明显作用. PMTS分子量及其用量对乳液的乳胶粒径、表面张力和粘度影响不明显. 但对于复合胶膜的性能来说, 三元复合乳液聚合物中PMTS分子量及其用量存在上限, 分子量上限值约为2000, 其用量上限约为PSU二元聚合物的10%, 在此之下PMTS的使用可以明显提高胶膜的力学及耐水性能.     

Preparation and characterization of waterborne polyurethanes modified with bis(3-(1-methoxy-2-hydroxypropoxy) propyl) terminated polysiloxanes

Polyurethanes(PU) were prepared using toluene diisocyanate,polypropylene glycol,ethylene glycol, dimethylolpropionic acid and triethylamine,and a siloxane modified PU(PSU) was obtained through reaction of the PU prepolymers with bis(3-(1-methoxy-2-hydroxypropoxy)propyl) terminated polysiloxanes(PMTS) of different molecular weight,specifically designed for this purpose.Results showed that,with increases in molecular weight of PMTS and its content,viscosity of the final PSU latexes decreased;phase separation of the incorporated PMTS in PSU films increased;the average particle sizes of the latexes varied between 110 nm and 330 nm,and the surface tension in the final latexes was relatively constant regardless of PMTS amount and its molecular weight.It was likely that copolymerized polysiloxanes had trend to enrich on top of the film when PMTS molecular weight was around 2000 and its content above 5 wt%.In general, PMTS modified polyurethane films showed higher performance than those from unmodified waterborne polyurethane latexes.     

氨丙基封端聚氰丙基甲基硅氧烷改性环氧树脂——两相相溶性及表界面形态研究

本文针对聚二甲基硅氧烷改性环氧树脂相溶性太差,性能不够理想等问题,提出用氰丙基替代部分甲基以减小聚硅氧烷与环氧树脂的溶度参数差,改善两相的相溶性。采用氨丙基封端的聚氰丙基甲基硅氧烷低聚体(表1)单独或与二乙烯三胺(固化剂)一同与双酚A环氧树脂反应,合成了一系列不同聚硅氧烷分子量和重量百分比的样品(表2)。并用示差扫描量热计(DSC)、动态力学谱(DMA)、光电子能谱(XPS)、接触角仪、扫描电子显微镜(SEM)、电子拉力试验机对其进行研究。结果表明在聚硅氧烷软段中引入氰丙基可提高两相的相溶性并使增韧效果明显改善。     

聚四氟乙烯、有机硅复合改性聚氨酯/环氧树脂共混聚合物的合成及其低表面能特性

以甲苯-2,4-二异氰酸酯(TDI)、聚醚二元醇为主要原料制得—NCO封端的预聚体,按一定比例和环氧树脂E-51混合均匀;另用氨乙基氨丙基甲基二甲氧基硅烷、八甲基环四硅氧烷(D4)合成一系列分子量不同的氨基聚硅氧烷,用多元胺作固化剂,并以聚四氟乙烯(PTFE)粉末为填料,合成一系列由PTFE、有机硅共同改性的聚氨酯/环氧树脂共混聚合物。测试了其力学性能、表面接触角、吸水率,同时进行了扫描电镜(SEM)以及表面电子能谱(ESCA)分析。结果表明:所制得的共混聚合物具有很低的表面能和良好的综合性能,PTFE和氨基聚硅氧烷对降低聚氨酯/环氧体系的表面能具有明显的复合效应。     

有机硅/蒙脱土复合改性聚氨酯弹性体的制备和性能

采用先将聚醚三元醇N330与有机蒙脱土(OMMT)研磨,制得N330/OMMT复合物,再将其与有机硅改性聚氨酯的预聚体混合的方法,以二甲硫基甲苯二胺(DMTDA)为固化剂,制备了有机硅/蒙脱土复合改性聚氨酯弹性体,并用FTIR对产物结构进行了表征.XRD和TEM表明,蒙脱土片层被撑开,并分散在基体中;SEM显示,加入蒙脱土后,有机硅与聚氨酯之间的相容性提高;TGA表明,有机硅和OMMT共同改性聚氨酯后,其耐热性比有机硅单一改性聚氨酯有所提高,并在OMMT含量为5 wt％时提高最大;DSC数据表明,在OMMT含量为5 wt％时,有机硅/蒙脱土复合改性聚氨酯弹性体的Tg明显升高.复合改性材料具有良好的表面性能和力学性能,其拉伸强度、断裂伸长率和硬度在OMMT含量为3 wt％时达到最大值.     

有机硅改性聚氨酯/纳米SiO2复合超疏水涂层的制备

以4,4'-二苯基甲烷二异氰酸酯(MDI)、聚四氢呋喃醚二醇(PTMEG)、羟基封端的聚二甲基硅氧烷(HO-PDMS)、1,4-丁二醇(BDO)为原料,合成了有机硅改性的聚氨酯溶液,通过核磁共振、红外光谱技术对其结构进行表征,并研究了羟基硅油加入量对聚氨酯热稳定性、疏水性的影响.以有机硅改性的聚氨酯溶液为基体、含氟硅烷偶联剂改性的纳米二氧化硅颗粒为填料,喷涂制备超疏水涂层,研究了填料添加量对复合涂层疏水性的影响.结果表明:当硅油加入量为9 wt%,填料加入量为60 wt%时,复合涂层性能最优,水接触角为153.3°,滞后角为6.3°.经过200℃加热1 h后,仍然具有大于150°的水接触角.对复合涂层进行磨损实验与防冰测试,结果表明:该复合涂层在磨损过程中,在基底暴露之前,整个涂层基体都具有超疏水性;并且该涂层能有效降低结冰温度,延长结冰时间,具有良好的防冰性能.     

含呱嗪聚硅氧烷聚脲聚氨酸及其离聚物的研究

以氨丙基封端聚二甲基硅氧烷及脲键改性聚硅氧烷低聚体分别与4，4－二异氰酸酯二苯甲烷（MDI)反应，并用1，4二（2－羟乙基）－呱嗪（N）扩链，合成了一系列含氮杂环聚氨酯共聚物。产物为透明热塑性弹性体，具有良好的成膜性能和宽阔的使用温区，通过碘乙烷和γ－丙磺酸内酯对上述样品进行季铵化，合成了阳离子型及双离子型离聚物。用傅里叶红外光谱（FT－IR）、示差量热分析（DSC）、动态力学谱（DMTA）、力学性能等方面对样品进行了表征。结果表明，在聚硅氧烷中引入脲键，提高了软、硬段两相的相容性。体系中既有软段间的氢键作用又有两相间的氢键作用，从而使这类材料的杨氏模量、抗张强度和断裂伸长均明显高于相应的聚二甲基硅氧烷聚脲聚氨酯体系。     

氨乙基氨丙基聚二甲基硅氧烷改性水性聚酯型聚氨酯的研究

由聚酯二元醇、异佛尔酮二异氰酸酯和二羟甲基丙酸合成聚氨酯预聚体，以氨乙基氨丙基聚二甲基硅氧(AEAPS)为扩链剂，制备了AEAPS改性聚氨酯水分散液。与未改性的聚氨酯水分散液相比，AEAPS改性聚氨酯水分散液的粒径增大，但粒径分布和表面张力基本不变，说明疏水的聚二甲基硅氧烷侧链被包裹于分散颗粒的内部；此外，改性聚氨酯水分散液的冻融稳定性显著增强。AEAPS改性聚氨酯水分散液成膜后，吸水率明显下降，水在膜表面的接触角增加，400℃时热失重下降，具有良好的疏水性和耐热性。     

氨基聚硅氧烷对改性环氧树脂的形态与性能的影响

将带有Ｎ－（β－氨乙基）－γ－氨丙基侧基的聚二甲基硅氧烷与环氧树脂共混,制备了聚硅氧烷改性环氧树脂固化物。研究了氨基聚硅氧烷的氨基含量对改性环氧树脂的形态和性能的影响。结果表明,改性环氧树脂固化物的形态与性能主要依赖于氨基聚硅氧烷的氨基含量,在环氧树脂中引入适宜氨基含量的氨基聚硅氧烷,可在一定程度上降低其模量,提高其柔性,并可明显改善环氧树脂的表面性能。     

环氧改性水性聚氨酯乳液的制备及其膜性能

以聚己内酯二元醇(CAPA)为软段,异佛尔酮二异氰酸酯(IPDI)和六亚甲基二异氰酸酯(HDI)为硬段,环氧树脂E-44为大分子交联剂,经相转化法合成了一系列环氧树脂改性负离子水性聚氨酯(EPPU)自乳化乳液,并制备了改性水性聚氨酯的固化膜.通过FTIR、TGA及接触角、力学性能测试对聚合物结构及其膜性能进行了研究.通过原子力显微镜(AFM)观察膜表面形态和表面粗糙度.乳液粒径及粒径分布通过动态激光光散射法(DLLS)测定.FTIR分析表明环氧树脂的羟基和环氧基都参与了发应.TGA表明,环氧树脂的加入可以提高聚氨酯的热稳定性.随着w(E-44)增大,改性聚氨酯膜的拉伸强度得到改善,断裂伸长率减小.随着w(E-44)增大,乳液粒径增大,薄膜的接触角增大,改性后的PU膜表面光滑度下降,拒水性增强.     

侧链为长链烷基醚的聚硅氧烷的合成及其药物控制释放性能的研究

通过硅氢加成法合成了侧链为长链烷基醚的聚硅氧烷及共聚物，研究了其相转变性质以及由其组成的共混硅橡胶薄膜对避孕药物（左旋十八甲基炔诺酮）的释放性能．结果表明：聚硅氧烷的熔融温度随侧链烷基的增长而提高；共聚硅氧烷的熔融温度随较长烷基的比例增加而提高；聚硅氧烷的侧链烷基呈侧向有序性排列．药物分子透过薄膜的速率及其温度依赖性与共混膜中侧链烷基的有序状态有关，即由晶态转变为非晶态时，药物的透过速率加快     

Liquid crystalline polyaniline and phthalocyanine-based polysiloxanes bearing lateral fluoro-substituted benzoic acid groups

A series of novel liquid crystalline polymers (PI, PII, PIII and PIV) containing lateral fluoro-substituted benzoic acid groups was synthesised using cholesteryl 4-(2-propenyloxy)-benzoate, 4-(allyloxy)-3-fluorobenzoic acid and poly(methylhydrogeno)siloxane. PI and PII showed smectic phase, but PIII and PIV showed chiral nematic phase due to more lateral fluoro-substituted benzoic acid groups in the polymer systems. Liquid crystalline polyaniline (PAN) and phthalocyanine (Pc)-based polysiloxanes showing chiral nematic phase were prepared by use of Pc, PAN and these liquid-crystalline polymers via hydrogen bond. PAN-based polysiloxanes showed different liquid crystalline behaviours from Pc-based polysiloxanes due to the difference of molecular structure. PAN-based polysiloxanes showed greater d-spacings between the side mesogenic groups than Pc-based polysiloxanes due to long rod-like geometrical shapes. Hydrogen bond based on lateral fluoro-substituted benzoic acid groups was formed to different geometrical shapes (strip or roundness) between PAN and Pc-based polysiloxanes.     

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.     

杯芳烃交联聚硅氧烷热稳定性能研究

聚有机硅氧烷是一类主链由硅-氧键连接而成,侧链为有机基团的聚合物,兼具有机聚合物和无机聚合物的特性,性能优异,尤以卓越的耐高温性能而著称,在大气中于-50~250℃可以长期使用[1].为了进一步提高聚有机硅氧烷的热稳定性,主要有以下几种方法,(1)添加各种耐热性添加剂,或可与聚     

Polysiloxanes with chlorobenzyl groups as precursors of new organic‐silicone materials

Various polysiloxanes bearing chlorobenzyl side groups were synthesized by the hydrolytic polycondensation of the 73:27 mol/mol mixture of [2‐(4‐chloromethylphenyl)ethyl] methyldichlorosilane and [1‐(4‐chloromethylphenyl)ethyl] methyldichlorosilane followed by the cationic equilibration or coequilibration with octamethylcyclotetrasiloxane, D₄. 1,3‐Divinyltetramethyl‐disiloxane was used as the chain end blocker to obtain a vinyl–Si ended chlorobenzyl‐substituted polysiloxane. In some cases, the polymer was additionally treated with dimethylvinylchlorosilane to achieve full substitution of chain ends by the vinyl group. Cohydrolysis of the chlorobenzylic monomer mixture with dimethyldichlorosilane was also practiced. Multiblock copolymers were obtained by polyhydrosilylation of the α,ω‐divinylsilyl chlorobenzyl‐substituted polysiloxanes with α,ω‐dihydrosilyl polydimethylsiloxanes. All these polymers and copolymers containing reactive chlorobenzylic groups were demonstrated to be convenient precursors of functional polysiloxanes of potential practical use. Some specific functional groups, such as quaternary ammonium salt groups of biocidal activity or azobenzene groups making the polymer sensitive to external stimuli by light, may be readily generated on polysiloxane under mild conditions. The chlorobenzylic substituted polysiloxanes may be also used as macroinitiators of the atom transfer radical polymerization, to obtain polysiloxanes with grafted organic polymers, such as styrene, 4‐chloromethylstyrene, and n‐butylacrylate. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1682–1692, 2004     

A method for reproducible preparation of chiral polysiloxanes with regular repeat units as stationary phases for capillary gas chromatography

Trifluoroethyl ester-functionalized polysiloxanes can be prepared by block condensation of 3-dichloromethylsilyl-2-methylpropionic acid 2′,2′,2′-trifluoroethyl ester with 1,5-bis(diethylamino)hexamethyltrisiloxane or with disodium tetramethyldisiloxane-1,3-diolate. The functionalized polysiloxanes may serve as supports for a variety of selector groups; for instance, nucleophilic displacements with L-valine-t-butylamide or L-α-naphthylethylamine lead to chiral polysiloxanes in high yields and with high reproducibility. Imidazole accelerates the rate of nucleophilic displacement. Capillary columns coated with such chiral polysiloxanes exhibit high enantioselectivity and thermostability.     

正离子光固化聚硅氧烷的合成及其环氧树脂复合固化膜的性能

以含氢聚硅氧烷(PMHS)分别与甲基丙烯酸六氟丁酯(HFMA)和烯丙基缩水甘油醚(AGE),经氯铂酸催化硅氢加成反应将甲基丙烯酸六氟丁酯和烯丙基缩水甘油醚引入聚硅氧烷的侧链,合成了3种含氟量不同的含氟代烃侧基/环氧侧基聚硅氧烷(EFPS),用FTIR、1H-NMR和13C-NMR进行了结构表征,将这类聚硅氧烷与环氧树脂...     

Synthesis of bis(3,3-dinitrobutyl)polysiloxanes

Phenyl groups were used as silicon-protecting groups in the synthesis of bis-(3,3-dinitrobutyl)polysiloxanes. The addition of diphenylsilane to acrolein dimethyl acetal, followed by reactions with methyllithium and phosphorus tribromide gave bis(3-bromobutyl)diphenylsilane. Sodium nitrite displacement gave bis(3-nitrobutyl)diphenylsilane, and oxidative nitration gave bis(3,3-dinitrobutyl)diphenylsilane. Dephenylation with bromine and hydrolysis gave cyclic polysiloxanes.     

Preparation and characterization of novel basic polysulfone polymers

Two synthesis routes for the preparation of novel base‐modified polysulfones (PSUs; Udel®) were investigated: (1) the addition of the basic aromatic ketones 2,2′‐dipyridylketone and 4,4′‐bis‐(diethylamino)benzophenone and the basic aromatic aldehydes N,N‐dimethylamino‐benzaldehyde, pyridine‐2‐aldehyde, pyridine‐3‐aldehyde, and pyridine‐4‐aldehyde to lithiated PSU and (2) the reaction of lithiated PSU with basic aromatic carboxylic acid esters such as 4‐N,N‐dimethylaminobenzoic acid ethylester, pyridine‐2‐carboxylic acid ethylester, pyridine‐3‐carboxylic acid ethylester, and pyridine‐4‐carboxylic acid ethylester. Both synthesis routes lead to a high degree of conversion, without the occurrence of crosslinking. This is remarkable, especially for the reaction of lithiated PSU with the ester compounds, because the ? (C?O)? Ar groups formed by the reaction of the ester with PSU–Li are not further converted with the remaining PSU–Li sites to (crosslinked) PSU? C(? OLi)? Ar? PSU alcoholates, as normally observed when esters are reacted with Li‐organic compounds. Starting with dilithiated PSU, we obtained degrees of substitution of 0.8–2 groups per PSU repeating unit. The structures and compositions of the modified PSU polymers were confirmed with NMR spectroscopy and elemental analysis. The modified polymers were also characterized via thermogravimetric analysis (thermal stability). Interestingly, the product of the reaction of lithiated PSU with 4,4′‐bis‐(diethylamino)benzophenone could be oxidized to a deep blue polymeric dye that showed proton self‐conductivity. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2874–2888, 2001