羟基聚甲基苯基硅氧烷的合成

四川大学的李强等人在酸性条件下水解甲基苯基二乙氧基硅烷，水解产物在碱催化下与D4开环聚合，制得了系列高苯基含量羟基封端的聚甲基苯基硅氧烷低聚物。     

羟基封端聚甲基苯基硅氧烷的制备及表征

以低摩尔质量的羟基硅油和甲基苯基环硅氧烷为原料、四甲基氢氧化铵[(CH3)4NOH]硅醇盐为催化剂,通过平衡共聚反应制备了羟基封端聚甲基苯基硅氧烷.研究了原料配比、催化剂用量、反应时间、反应温度等因素对聚合物制备的影响.通过红外光谱,热裂解气质联用等方法对制备的产物进行了结构表征.结果表明,当(CH3)4NOH质量分数为0.04%, 反应温度110 ℃,反应时间为6 h,甲基苯基硅氧链节与二甲基硅氧链节的量之比为1:1,可制得不同苯基含量的羟基封端聚甲基苯基硅氧烷.     

硅氧烷/聚氨酯复合乳液的制备

将水性聚氨酯(WPU)作为大分子乳化剂并以易水解缩合的3-甲基丙烯酰氧丙基三甲氧基硅烷(MPS)为单体,通过乳液聚合成功合成出以聚氨酯为壳、聚硅氧烷(PMPS)为核的一系列不同PMPS(由MPS单体聚合而成)含量的稳定的WPU/PMPS复合乳液,且PMPS的最高含量能达到50%(基于乳液中不挥发组分的质量分数)时,复合乳液也很稳定。通过透射电镜(TEM)发现复合乳液粒子的核壳结构很明显,动态光散射(DLS)测定了乳液的粒径分布,Zeta电位测试表明了乳液稳定性与MPS加入量有关,固体29Si核磁谱图证实了WPU/PMPS复合乳液在室温下成膜时,PMPS会发生水解缩合反应,并在WPU涂膜中生成Si—O—Si交联型的无机结构。     

低粘度羟基封端聚甲基苯基硅氧烷的合成研究

以甲基苯基环硅氧烷(MPCS)和乙酸酐为原料,在大孔径强酸性阳离子交换树脂催化下开环聚合制备了乙酰氧基封端的聚甲基苯基硅氧烷(AcO-PMPS),AcO-PMPS在Na2CO3水溶液中水解制备了低粘度羟基封端的聚甲基苯基硅氧烷(HO-PMPS).研究结果显示,优化的聚合反应条件为:催化剂质量分数为18％～20％,反应温...     

端羟基聚甲基苯基硅氧烷低聚物的合成与表征

以甲基苯基二甲氧基硅烷为原料,在盐酸催化下,在过量水中进行水解缩聚反应,得到端羟基聚甲基苯基硅氧烷。采用红外光谱、核磁共振谱和飞行时间质谱对产物进行了表征,并探讨了水解缩聚机理。结果表明,产物是以四聚体为主的端羟基聚甲基苯基硅氧烷,平均相对分子质量为862。     

紫外线吸收剂UV-P的合成和应用

介绍了UV-P的合成方法，即：将2-硝基苯胺(1)用亚硝酸钠(2)和盐酸重氮化后与4-甲基苯酚(3)进行偶合反应制成2-硝基-2′-羟基-5′-甲基偶氮苯(4)。(1)、(2)、(3)的摩尔比为1：1．05：1。将(4)用水合肼还原为2-(2′-羟基-5′-甲基苯基)苯并三唑N-氧化物(5)，然后再用锌粉还原(5)为2-(2′-羟基-5′-甲基苯基)苯并三唑(UV-P)。该类产品与受阻胺光稳定剂(HALS)并用于PP、PE、PVC、PS时，有协同效应，效果随材料不同而异。     

l—（2—羟基—5—甲基苯基）苯乙胺的合成

对甲基苯酚与苯乙酰氯酸化得到苯乙酸(4-甲基)苯酸；然后在三氯化铝作用下重排得到苄基(2-羟基-5-甲基)苯基酮；此酮经硫酸二甲酸甲基化得到苄基(2-甲氧基-5-甲基)苯基酮，再和甲酸铵反应得到1-(2-甲氧基-5-甲基苯基)苯乙胺，最后经氢溴酸水解得到1-(2-羟基-5-甲基苯基)苯乙胺。所有中间体和最终产品的结构均由IR、元素分析、1HNMR得到证实。     

1-甲基-3-苯基哌嗪的合成

研究了1 甲基 3 苯基哌嗪的合成工艺。以N 甲基乙醇胺和环氧苯乙烷为起始原料,在80℃下反应4h,得到N (2 羟乙基) N 甲基 α 羟基 β 苯乙基胺,在0～10℃下将其滴加入氯化亚砜,并在45℃下反应2h,生成N (2 氯乙基) N 甲基 α 氯 β 苯乙基胺,通入过量HCl,得其盐酸盐,在40～45℃下再加入氨水反应3h,经减压蒸馏,重结晶得到目标化合物1 甲基 3 苯基哌嗪,总收率43 9%。目标化合物结构经核磁共振分析验证。     

1-(2-羟基-5-甲基苯基)苯乙胺的合成

对甲基苯酚与苯乙酰氯酯化得到苯乙酸 ( 4 -甲基 )苯酯 ;然后在三氯化铝作用下重排得到苄基 ( 2 -羟基 -5 -甲基 )苯基酮 ;此酮经硫酸二甲酯甲基化得到苄基 ( 2 -甲氧基 -5 -甲基 )苯基酮 ,再和甲酸铵反应得到 1-( 2 -甲氧基 -5 -甲基苯基 )苯乙胺 ,最后经氢溴酸水解得到 1-( 2 -羟基 -5 -甲基苯基 )苯乙胺。所有中间体和最终产品的结构均由IR、元素分析、1 HNMR得到证实。     

废甲基苯基硅油的回收利用

以黑褐色不流动粘稠状的废甲基苯基硅油、八甲基环四硅氧烷、六甲基二硅氧烷为原料，制成了甲基苯基硅油。探讨了催化剂的种类及用量、反应温度、反应时间对产物性能的影响。建立了采用废甲基苯基硅油制备甲基苯基硅油的工艺：催化剂Ⅰ的用量为0．3％～0．6％，催化剂Ⅱ的用量为1．0％，添加催化剂Ⅰ时的温度为130～150℃，平衡反应温度105～120℃，平衡反应时间6～8h。按此工艺制备的甲基苯基硅油．其各项性能指标均达到255—150A甲基苯基硅油的技术指标。     

有机硅改性松香基环氧树脂的制备及阻燃性能

制备了聚甲基苯基硅氧烷（PMPS）改性松香基乙二醇二缩水甘油醚AR-EGDE。红外光谱(IR)、核磁共振（¹³C NMR）和环氧值测试结果表明有机硅成功接枝至环氧树脂。同时,将PMPS与AR-EGDE充分混合得到物理改性树脂。通过力学性能和极限氧指数测试探讨了改性方法对改性树脂力学及阻燃性能的影响：化学改性优于物理改性及未改性的AR-EGDE。热失重、炭层分析表明,PMPS改性的树脂在受热和燃烧过程中,都能形成含硅炭层,该炭层可延缓内部材料热分解,同时阻止可燃裂解气体的释放和熔滴发生,从而提高材料的耐热和阻燃性能。物理改性松香基环氧,燃烧时无法形成有效富硅炭层覆盖于底部材料,从而使其阻燃性劣于化学改性。     

Preparation and thermal properties of Alkoxy Silane functionalized polyether sulfone/well‐defined poly(trimethoxysilyl) propyl methacrylate‐based hybrid materials

In this study, novel polyethersulfone (PES) and poly(trimethoxysilyl) propyl methacrylate (PMPS) containing hybrid materials were prepared. PES was functionalized with trimethoxysilane groups by UV‐induced grafting reaction. PMPS was synthesized by atom transfer radical polymerization. In the followed process, the functionalized PES mixed with different amount of PMPS, thermally treated to promote sol–gel crosslinking process to prepare the PES‐based hybrid materials. The trimethoxysilane grafted PES chains are covalently bonded with the well‐defined trimethoxysilane groups of PMPS. The chemical structure of the prepared PES and PMPS is confirmed by Fourier transform infrared analysis. The morphology of the hybrids was investigated by scanning electron microscopy. The results of thermogravimetric analysis show that the thermal stability of the hybrid materials was significantly affected with the addition of PMPS. POLYM. ENG. SCI., 58:1346–1352, 2018. © 2017 Society of Plastics Engineers     

Synthesis and characterisation of poly(arylene sulphides): Part 10. A comparative evaluation of the thermoanalytical behaviour and curing of poly(1,4-phenylene sulphide) and copolymers containing 1,4-phenylene sulphide and 2-methyl-1,4-phenylene sulphide repeat units

Thermogravimetry, differential scanning calorimetry and curing studies were used to assess the viability of random and block copolymers comprising 1,4-phenylene sulphide and 2-methyl-1,4-phenylene sulphide repeat units as alternatives to poly(1,4-phenylene sulphide) (PPS). The properties of the copolymers are discussed critically and compared with those of the parent homopolymers PPS and poly(2-methyl-1,4-phenylene sulphide) (PMPS). The results suggest that (a) random copolymers with low PMPS contents would offer the best compromise between PPS and PMPS properties, and (b) more desirable physical properties might be achieved from systems containing a less reactive 2-substituted-1,4-phenylene sulphide comonomer repeat unit.     

RAFT聚合制备PMPS-b-PNIPAM嵌段共聚物及温敏性纳米粒子

利用可逆加成-断裂链转移(RAFT)活性自由基聚合合成了一系列分子量可控、分子量分布窄的甲基丙烯酸-3-三甲氧基硅丙酯(MPS)和N-异丙基丙烯酰胺(NIPAM)的嵌段共聚物，在水溶液中分散制备温敏性的含硅纳米粒子。保持疏水链段PMPS的长度恒定，改变亲水链段PNIPAM的长度，在不同pH的水溶液中进行实验，研究亲水链段长度、pH对聚合物的临界聚集浓度、纳米粒子的尺寸和形貌以及温度变化过程中的相分离行为的影响，得到尺寸较小、溶液稳定的温度响应性含硅纳米粒子，同时具有有机物和无机物的优良特点，在生物医学、化学催化、纳米反应器、染料涂料等多领域具有广泛的应用前景。     

有机硅改性环氧树脂的合成与性能

热熔法制备了系列聚甲基苯基硅氧烷(PMPS)改性环氧树脂,通过环氧值、红外光谱(IR)和凝胶色谱(GPC)分析表明,有机硅接枝到了环氧树脂上,且环氧基保持不变。探讨了改性方法、有机硅含量对改性树脂固化体系的微观形态、韧性及耐热性的影响。实验表明,当m(E-20)∶m(DC-3074)=7∶3时,化学改性树脂固化体系的韧性和耐热性能明显提高,玻璃化转变温度(Tg)为88.33℃,质量损失50%时的热分解温度(Td)为487.80℃,分别比物理改性环氧树脂提高了52.63℃和36.75℃,同时此改性树脂固化物还具有优良的涂膜性能。     

有机-无机杂化核壳型乳胶粒的制备及其粒径控制

以苯乙烯乳液聚合合成种子,再在种子外生成苯乙烯与甲基丙烯酸-3-三甲氧基硅丙酯（MPS）的共聚物,利用MPS中硅氧烷基的水解-缩合反应,形成交联的壳,得到有机-无机杂化型核壳乳胶粒.然后用溶剂将聚苯乙烯模板溶解,可得到空心微胶囊.通过透射电镜（TEM）和动态光散射粒径仪（DLS）观测乳胶粒及微胶囊的形态.并研究了乳化剂种类、介质pH值、MPS用量和加入方式对粒径、粒子数和体系稳定性的影响.发现非离子型乳化剂、酸性或碱性介质、MPS用量过多均促进乳胶粒子数减少,减弱了乳液稳定性.而采取连续滴加MPS的方法则可提高乳液的稳定性,且粒径可控.     

有机硅琥珀酸酯表面活性剂的合成与表征

以醇胺硅油(PAPS)和马来酸酐(MA)为原料,在对甲苯磺酸(PTSA)的催化作用下,通过开环反应合成了一种新型有机硅琥珀酸酯(PMPS)表面活性剂。通过单因素实验优化出PMPS合成条件:原料n(MA)∶n(PAPS)=1.00∶0.31,反应温度90℃,w(PTSA)=0.6%(以PAPS质量计),反应时间4.5 h。通过综合热分析测试了PMPS的热分解温度Tg为192.8℃,测定了PMPS的临界胶束浓度CMC为0.12 g/L。     

Synthesis of polysilane-acrylamide copolymers by photopolymerization and their application to polysilane-silica hybrid thin films

Various polysilane-acrylamide block copolymers have been prepared from photopolymerization of acrylamide-type monomers using poly(methylphenylsilane) (PMPS) as a macro-photo-radical initiator. The acrylamide block in the copolymers improved the hydrophilic property of PMPS. These PMPS-acrylamide block copolymers have been applied to formation of PMPS-silica hybrid thin films via sol-gel reaction. Homogeneous and transparent PMPS-silica hybrid thin films were obtained from a few PMPS-acrylamide block copolymers. It was found for these hybrid thin films based on hydrogen bonding formation between amide group and silanol group. The surface properties of hybrid thin films were evaluated by water contact angle measurement, scanning electron microscope (SEM), and atomic force microscope (AFM) images.     

Linear polymers with sulfur in the main chain III. Synthesis of polythioesters by polycondensation of bis(4,4′‐mercaptophenyl)sulfide with various acid dichlorides and their properties

Synthesis and properties of sulfur‐containing linear polythioesters derived from bis(4,4′‐mercaptophenyl)sulfide (MPS) and various acid dichlorides (AC) have been studied to evaluate the effect of the thioester group in comparison with corresponding linear polyesters. Polycondensations between MPS and azelaoyl chloride (AZC) chosen as a model reaction system were investigated under various conditions by solution polycondensation, to find optimal conditions to get high molecular weight and quantitative yield. The obtained polymer using chloroform as a solvent indicated the highest molecular weight, determined by gel permeation chromatography (GPC). Thus the polythioesters from MPS and AC were synthesized under the above‐mentioned conditions. The thermal properties of polythioesters including the MPS moiety were evaluated by thermogravimetry/differential thermal analysis (TG/DTA), and differential scanning calorimetry (DSC). Those indicated that the polythioesters including the MPS moiety were crystalline polymers with relatively high heat resistance. These polythioesters were found to show an odd–even effect with the glass transition temperature, melting point, and oxygen permeability based on the methylene numbers. The tensile strength and storage modulus decreased with the number of methylene units. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 508–515, 2005     

Effect of pendant group of polysiloxanes on the thermal and mechanical properties of polybenzoxazine hybrids

Polybenzoxazine (PBa) was successfully hybridized with polysiloxanes by synchronizing two reactions; ring-opening polymerization of benzoxazine (Ba) and sol–gel process of diethoxysilanes. Diethoxydimethylsilane, diethoxymethylphenylsilane, and diethoxydiphenylsilane were used as precursors for the formation of polydimethylsiloxane (PDMS), polymethylphenylsiloxane (PMPS), and polydiphenylsiloxane (PDPS), respectively. The effect of pendant group of polysiloxane on the optical, mechanical, and thermal properties of PBa–polysiloxane hybrids was studied. The progress of sol–gel process was confirmed by IR, ¹H NMR and size exclusion chromatography. Opaque PBa–PDMS hybrid films were obtained up to 15 wt% of PDMS content, corresponding to the phase separation with 1–2 μm domain size of PDMS as observed from the scanning electron microscope. Meanwhile, transparent PBa–polysiloxane hybrid films were obtained up to 29 wt% for PMPS and 36 wt% for PDPS, which revealed no apparent domain of PMPS and PDPS, indicating high compatibility of the polysiloxanes with PBa. Dynamic viscoelastic analysis (DMA) of the PBa–PDMS hybrid revealed two glass transition temperatures corresponding to PDMS and PBa components, while the DMA of the PBa–PMPS and PBa–PDPS hybrids revealed only one glass transition temperature. The tensile strength and elongation at break of the hybrid films increased with increasing polysiloxane content. Thermogravimetric analysis revealed high weight residue at 850 °C for PBa–polysiloxanes with phenyl group.