聚甲基苯基硅烷及其共聚物的合成与表征

用格氏法合成了甲基苯基二氯硅烷,并用钠缩合法将它均聚或分别与二甲基二氯硅烷、二苯基二氯硅烷、甲基乙烯基二氯硅烷等共聚,合成了４种聚硅烷。用ＩＲ、ＵＶ、＾１Ｈ－ＮＭＲ和ＧＰＣ对它们进行了表征。     

聚甲基环戊二烯基硅烷及其共聚物的合成与表征

用钠试剂法合成了甲基环戊二烯基二氯硅烷,采用钠缩合法将其均聚,并分别与二甲基二氯硅烷、二苯基二氯硅烷、甲基苯基二氯硅烷及甲基正丁基二氯硅烷进行共聚反应,合成了5种聚硅烷。并用IR、UV、^1H NMR、GPC和荧光光谱对它们进行了表征。     

甲基二氯硅烷的化学反应及其综合利用

简述了甲基二氯硅烷的硅氢化反应、热缩合反应、水解反应和醇解反应，及其重要反应产物甲基氯丙基二氯硅烷、甲基乙烯基二氯硅烷、甲基三氟丙基二氯硅烷、甲基苯基二氯硅烷、甲基含氢环体和含氢硅油的制备和应用。     

聚二烷基硅烷的合成及其表征

以二甲基二氯硅烷、二苯基二氯硅烷为原料，通过Wurtz还原反应合成出聚二甲基硅烷、聚二苯基硅烷，并用UV、^1H NMR、FT—IR以及GPC、DSC—TGA等方法进行了光谱分析和结构表征。     

分子设计在聚硅烷合成中的应用

采用分子设计的方法、通过理论计算,从分子结构学的角度解释了聚二甲基硅烷和聚甲基氢硅烷分子结构相似、但特性各异的原因。即聚甲基氢硅烷分子两个相邻扭曲角在势能最低点时的扭曲范围较大,其势能较大的区间较小,在大部分区域内聚甲基氢硅烷分子从一个构象转到另一个构象所需克服的势能很小;因此,聚甲基氢硅烷分子在有机溶剂中的伸展性好,溶解性好。相反,聚二甲基硅烷分子的势能在较大范围内都较高,聚二甲基硅烷分子的构象要到达这样的位置很困难;因此,聚二甲基硅烷的溶解特性较差。通过计算不同聚硅烷的势能面,可初步判断其溶熔特性的好坏。     

二茂铁高温催化合成甲基苯基二氯硅烷的研究

以二茂铁为催化剂先驱体、氯苯与甲基氢氯硅烷为反应物,采用气相缩合法合成了甲基苯基二氯硅烷。研究了二茂铁用量对甲基苯基二氯硅烷含量的影响。气质分析表明:产物中主要含甲基三氯硅烷、苯、氯苯、甲基苯基二氯硅烷、联苯等。适量添加二茂铁能显著提高产物中甲基苯基二氯硅烷的含量,添加10 g二茂铁(占原料质量的0.88%)时,产物中甲基苯基二氯硅烷的质量分数达到20.73%,比未加二茂铁时提高了16.77个百分点;但不宜过多,否则管式反应器会发生严重堵塞。     

聚甲基(对甲苯基)硅烷的合成与荧光性质

采用钠缩合法，将甲基(对甲苯基)二氟硅烷进行均聚，或分别与二甲基二氟硅烷、甲基苯基二氯硅烷、二苯基二氯硅烷进行共聚，合成了4种聚硅烷。用^1HNMR、IR、GPC进行了结构表征，并研究了聚硅烷固体和溶液的荧光性质。结果表明，聚硅烷的聚集态和构象对其荧光性质有较显著的影响。苯基对位甲基的给电子效应使最大荧光发射波长(λmax)略有红移；侧基的共轭作用和分子对称性可能也对其固体和溶液的λmax有较大影响；链长较长的聚硅烷荧光强度较大。     

甲基三氯硅烷、甲基乙烯基二氯硅烷、甲苯的二元及三元体系等压汽液平衡

引　言甲基乙烯基二氯硅烷是重要的有机硅单体和硅烷偶联剂 ,在硅橡胶、涂料、印染、化妆品等领域有着广泛的应用 .在合成甲基乙烯基二氯硅烷的过程中 ,甲苯作为均相催化剂的载体以及反应的媒介体循环使用 ,甲基三氯硅烷是副产物 ,在分离过程的设计中需要有关甲基三氯硅烷、甲基乙烯基二氯硅烷、甲苯体系的汽液平衡数据 ,此前文献尚未见报道 .为了满足过程开发与工程设计的需要 ,本研究测定了甲基三氯硅烷、甲基乙烯基二氯硅烷和甲苯三元体系及其 3个二元体系的相平衡数据 ,并进行了热力学关联 .1　实验部分1 1　试　剂甲基三氯硅烷 :江西蓝…     

用作陶瓷先驱体的可溶性聚硅烷的合成与表征

以甲基氢二氯硅烷、二甲基二氯硅烷为原料，利用均聚和共聚的方法，合成了几种不同组成的可溶性聚硅烷，研究了反应条件对可溶性聚硅烷产率的影响，并用IR、XRD对产物进行了表征。结果表明：甲基氢二氯硅烷在反应体系中的比例越高，可溶聚硅烷的产率越高，增加反应时间和降低反应温度可提高可溶聚硅烷的产率。     

萘基甲基二氯硅烷和二苯基二氯硅烷共聚物

湖北大学的雷艳秋等人用格氏法合成了α-萘基-甲基二氯硅烷；并采用钠缩合法将其与二苯基二氯硅烷反应，合成了α-萘基-甲基硅烷与聚二苯基硅烷的共聚物；该聚合物具有良好的热稳定性，在紫外区产生较强的紫外吸收和荧光发射。     

Effect of self‐nucleation on the crystallization of segmented copolymer poly(ether ester)

The effect of self‐nucleation on the nonisothermal and isothermal crystallization behaviors of the segmented copolymer poly(ether ester), based on poly(ethylene glycol) as the soft segment and poly(ethylene terephthalate) as the hard segment was investigated by means of differential scanning calorimetry (DSC) and depolarization polarized light (DPL) techniques, respectively. The results demonstrated that self‐nucleation could enhance the crystallization rate in both cases. The experimental conditions of the self‐nucleation procedure studied by DSC were discussed in detail. The isothermal crystallization was analyzed by the Avrami equation, and the Avrami parameters were dependent on the melting temperature. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 498–504, 2001     

聚乙二醇/聚(β-羟基丁酸酯)两嵌段共聚物的合成及表征

为改进聚(β-羟基丁酸酯)(PHB)的结晶性和亲水性,通过聚乙二醇单甲醚(MPEG)的端酰氯基团和聚(β-羟基丁酸酯)的端羟基基团的官能团反应,制备了聚乙二醇/聚(β-羟基丁酸酯)两嵌段共聚物。通过红外光谱、核磁、X射线衍射、差热分析和凝胶渗透色谱等手段,证明制备了嵌段共聚物。吸水实验表明,材料的亲水性得到了明显的改善。     

Spherulitic crystallization in blends of poly(ethylene oxide) and poly(methyl methacrylate)

The crystallization kinetics of binary blends of poly(ethylene oxide) and poly(methyl methacrylate) were investigated. The isothermal spherulitic growth rates were measured by means of a polarized light microscope. The temperature and composition dependence on the growth rates have been analysed. The temperature range studied was from 44° to 58°C. The introduction of poly(methyl methacrylate) into poly(ethylene oxide) resulted in a reduction of the spherulitic growth rate as the proportion of poly(methyl methacrylate) was increased from zero to 40% by weight. Results have been analysed using the theoretical equations of Boon and Azcue for the growth rate of polymer-diluent mixtures. The experimental results are in good agreement with this equation. The temperature coefficient is negative as is the case in the crystallization of bulk homopolymers.     

聚乙二醇/聚(β-羟基丁酸酯)/聚乙二醇三嵌段共聚物的合成与表征

为改进聚(β-羟基丁酸酯)(PHB)的结晶性和亲水性,通过聚乙二醇单甲醚(MPEG)的端酰氯基团和聚(β-羟基丁酸酯)的端羟基基团的官能团反应,制备了聚乙二醇/聚(β-羟基丁酸酯)/聚乙二醇三嵌段共聚物。通过红外光谱、核磁、X-射线衍射、差热分析和凝胶渗透色谱等手段,证明制备了嵌段共聚物。吸水实验表明,材料的亲水性得到了明显的改善。     

聚乙烯醇/聚乙二醇复合材料的热塑加工性能

通过热塑加工方法制备了增塑改性聚乙烯醇(mPVA)/聚乙二醇(PEG)复合材料,研究了PEG相对分子质量和含量对mPVA/PEG复合材料热性能、热塑加工性能,转矩流变性能和力学性能的影响.结果表明:加入适量PEG可降低mPVA的熔点,表明PEG对mPVA有一定的增塑作用;随着PEG用量的增加,mPVA的熔体流动速率增大...     

Binary blends based on poly(N‐isopropylacrylamide): Miscibility studies with PVA,PVP, and PAA

Blends of poly(vinyl alcohol) (PVA), poly(acrylic acid), (PAA), and poly(vinyl pyrrolidone) (PVP), with poly(N‐isopropylacrylamide) (PNIPAM), were prepared by casting from aqueous solutions. Mechanical properties of PNIPAM/PVA blends were analyzed by stress–strain tests. Differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) were employed to analyze the miscibility between the polymeric pairs. The results revealed that PNIPAM is not miscible with PVA and PVP in the whole range of composition. On the other hand, PNIPAM interacts strongly with PAA forming interpolymer complex due to the formation of cooperative hydrogen bonds. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 743–748, 2004     

Self-Assembly of Methyl Substituted Polyaniline Hollow Nanospheres in a Polyelectrolyte Solution

Hollow nanospheres of poly(m-toluidine), poly(o-toluidine), and poly(N-methylaniline) were successfully prepared in a solution of poly(methyl vinyl ether-alt-maleic acid) by using ammonium persulfate as the oxidant. The polymerization processes of methyl substituted aniline were monitored by recording pH and temperature changes of the reaction medium. The experimental results showed that the substitution position of methyl group affected the characteristics of formed hollow nanospheres. The formation mechanism of such hollow nanospheres was suggested. The produced hydrophobic oligomers self-assembled at the interface of water/droplet of monomers and acted as the soft template for the formation of hollow spheres.     

Phase Behaviour of Poly(ethylene oxide)/Poly(styrene-co-maleic anhydride) Blends

Thermal behaviour and morphology of blends of poly(ethylene oxide) (PEO) and poly(styrene-co-maleic anhydride) (SMA) prepared by the coprecipitation technique were studied by means of differential scanning calorimetry, optical microscopy and thermogravimetry. SMA containing 25wt% maleic anhydride (MA) was found to be miscible with PEO when the SMA content was greater than 80%. The melting temperature and crystallinity depended on the composition of the blend. SMA appears to segregate interlamellarly during the isothermal crystallization of PEO. The thermal stability of blends was enhanced and was higher than that of pure PEO and SMA. © of SCI.     

有机聚硅氧烷接枝聚醋酸乙烯酯的研究

本工作合成了聚二甲基硅氧烷—8—聚醋酸乙烯酯,通过红外光谱、核磁共振光潜、电子显微镜照相等技术表征了接枝共聚物结构。研究了接枝率与反应时间、分子量大小、引发剂用量的关系。     

Preparation and characterizaton of poly(dimethyl amino ethyl methacrylate) modified poly(vinyl alcohol) membrane by UV radiation for the permeation of 5‐fluorouracil

Poly(vinyl alcohol) was modified by UV radiation with dimethyl amino ethyl methacrylate (DMAEMA) monomer to get poly(dimethyl amino ethyl methacrylate) modified poly(vinyl alcohol) (PVADMAEMA) membrane. The PVADMAEMA membranes were characterized by Fourier transform infrared spectroscopy. The tensile strength and elongation of PVADMAEMA membranes were measured by Universal Testing Machine. The results of X‐ray diffraction (XRD) and differential scanning calorimetry (DSC) showed that (1) the crystalline area in PVADMAEMA decreased with increasing the content of poly(dimethyl amino ethyl methacrylate) in the membrane. (2) Only one glass transition temperature (T_g) was found for the various PVADMAEMA membranes. It means that poly(dimethyl amino ethyl methacrylate) and PVA are compatible in PVADMAEMA membrane. (3)The T_g of the membrane is reduced with increasing the content of poly(dimethyl amino ethyl methacrylate) in the membrane. The water content on the PVADMAEMA membranes was determined. It was found that the water content on the PVADMAEMA membrane increased with increasing the content of poly(dimethyl amino ethyl methacrylate). The changes of properties enhanced the permeability of 5‐Fluorouracil (5‐Fu) through the PVADMAEMA membranes. A linear relationship between the permeability and the weight percent of poly(dimethyl amino ethyl methacrylate) in the PVADMAEMA membrane is found. It is expressed as P (cm/s) = (9.6 ± 0.4) × 10^?5 + (8.8 ± 0.6) × 10^?5 W _x , where P is the permeability of 5‐Fu through the membrane and W_x is the weight percent of poly(dimethyl amino ethyl methacrylate) in the PVADMAEMA membrane. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012