液体色谱,凝胶色谱分析低聚芳砜及其双烯大分子单体

本文用液相色谱和凝胶色谱对双酚A、双酚S型低聚芳砜及α,ω-双甲基丙烯酸聚芳砜酯大分子单体进行了组分分析,通过改合成条件、测定数均分子量等辅助手段确定液相色谱各峰的归属,计算其分子量及分子量分布指数,并对两种方法测定的结果进行了比较。用液相色谱观察低聚体每个组分的含量及其反应过程中的消长情况比凝胶色谱清晰。     

聚苯醚砜在二甲基甲酰胺中稀溶液性质的研究(Ⅰ)

本文用粘度和小角光散射法确定了聚苯醚砜(PPES)25℃时θ溶剂的组成(DMF与C_2H_5OH的体积比为81.5:18.5)。表征了PPES链的柔性参数A=(r_0~2/M)~(12)=0.0864 nm,C_∞=r_0~2/nl~2=2.5。订定PPES在DMF中25℃的MHS方程为[η]=0.0499 M~(0.63),与Allen的结果不同。得到了第二维利系数A_2与重均分子量的关系为A_2=0.0375 M~(-0.36),还测定了PPESDMF体系的Huggins参数X_1。     

羧化聚苯醚与聚苯乙烯共混体系相分离初期分子量影响的光散射研究

 本文用激光光散射方法研究了具有特殊相行为[(低临界溶解温度(LCST),高临界溶解温度(UCST)共存]共混体系羧化聚苯醚和聚苯乙烯在UCST域内的不稳相分离初期分子量对动力学参数的影响。结果表明:相分离初期动力学过程与Cahn理论吻合;随着分子量增加,表现扩散系数D_app明显减小;该体系的表现扩散系数为10^-14 cm²s^-1数量级。deGennes管子模型可很好地描述不稳相分离初期大分子扩散行为。     

羧化聚苯醚与聚苯乙烯共混体系相分离初期分子量影响的光散射研究

本文用激光光散射方法研究了具有特殊相行为[(低临界溶解温度(LCST),高临界溶解温度(UCST)共存]共混体系羧化聚苯醚和聚苯乙烯在UCST域内的不稳相分离初期分子量对动力学参数的影响。结果表明:相分离初期动力学过程与Cahn理论吻合;随着分子量增加,表现扩散系数D_(a??)明显减小;该体系的表现扩散系数为10~(-14) cm~2s~(-1)数量级。deGennes管子模型可很好地描述不稳相分离初期大分子扩散行为。     

亚砜还原法合成聚苯醚硫醚的结构与性能研究

以氟苯和氯化亚砜反应合成了4,4’-二氟二苯亚砜,并将其与4,4’二羟基二苯硫醚在N-甲基吡咯烷酮溶剂中进行亲核取代反应合成了聚苯醚硫醚醚亚砜,用乙二酰氯/四丁基碘化铵还原该亚砜聚合物制备了聚苯醚硫醚。用红外光谱和核磁共振谱对合成单体的结构进行了确认,同时对聚合物进行了红外光谱、核磁共振、元素分析、X射线光电子能谱、X射线衍射、DSC分析、TG/DTG以及溶解性测试。结果表明聚苯醚硫醚样品具有氧醚和硫醚交替的线性结构,特性粘度为0.55 dL/g的PPSE熔点达236℃,在氮气条件下,样品起始分解温度和最大分解速率处温度分别为359℃和514℃,在700℃时的重量保留率为43.3%,且在加热条件下能溶解于N-甲基吡咯烷酮(NMP)、二甲基乙酰胺(DMAc)、二甲基甲酰胺(DMF)等极性有机溶剂中。     

聚苯醚砜在二甲基甲酰胺中稀溶液性质的研究(Ⅱ)

本文用广角及准弹性光散射法测定了聚苯醚砜各级分在DMF中和在θ溶剂中25℃时的均才半径R_G,第二维利系数A_2,流体力学半经R_H,扩散系数D_O,扩散系数的浓度依赖性k_F以及这些参数与分子量M的关系。它们的结果如下R_G=0.031MO~(0.55) D_O(θ)=0.906×10~(-4)M~(0.5) D_0=1.445×10~(-4)M~(0.55)A_2=0.033M~(-0.35) k_D(θ)=0.5M~(0.34) k_D=2.3×10~(-6)M~(1.36)α_H=R_H/R_H(θ)=0.63M~(0.05)R_H(θ)=0.0299M~(0.5)R_H=0.0188M~(0.55) 作者讨论了静态与动态两种高分子尺寸之间的关系;三种溶胀因子α_η和、α_H、α_G之间的关系;以及摩擦系数的浓度系数k_F与流体力学体积V_H之间的关系。它们的结果满足下面各关系式: R_H/R_G=[π(v+1)(2v+1)/3]~(1/2)(2-v)(1-v)/2, α_η~3=α_(G)~2α_H, k_F=1.2A_2M+N_AV_H/M,K_F(θ)=N_AV_H/M     

测定含甲基丙烯酰氧端基大分子单体分子量的新方法

建立了用紫外分光光度法测定含甲基丙烯酰氧端基大分子单体数均分子量的新方法 .在本实验条件下 ,以 95%乙醇∶THF( 7∶3 )为溶剂 ,在最大吸收波长 2 1 3nm处对含甲基丙烯酰氧端基的聚四氢呋喃大分子单体进行定量分析 ,所得结果与端基滴定分析法所得结果最大相对误差小于± 5% ,用t检验法对两法测定结果差别进行显著性检验 ,两法所得结果差别无显著意义 .紫外分光光度法可成为一种表征含甲基丙烯酰氧端基大分子单体数均分子量的方便方法 .     

酚酞型聚芳醚砜 Ⅳ.含羧基聚芳醚砜的合成

离子性聚合物的合成方法主要集中于通过一些含芳环聚合物的大分子反应,引入不同的离子基。如聚苯乙烯、聚芳醚砜、聚芳醚酮的磺化反应及聚苯醚的羧化反应等。但伴随大分子反应,聚合物要发生严重的化学降解,并且引入离子基团数目也不易控制。 本工作将酚酞啉引入酚酞型聚芳醚砜,发现在弱碱K_2CO_3体系中酚酞啉仍能保持一定的反应活性,且不至于发生交联反应。通过与酚酞的共聚反应可方便地控制聚合物的羧化度。     

测定含甲丙烯酰氧端基大分子单体分子量的新方法

建立了用紫外分光光度法测定含甲基丙烯酰氧端基大分子单体数均分子量的新方法 .在本实验条件下 ,以 95%乙醇∶THF( 7∶3 )为溶剂 ,在最大吸收波长 2 1 3nm处对含甲基丙烯酰氧端基的聚四氢呋喃大分子单体进行定量分析 ,所得结果与端基滴定分析法所得结果最大相对误差小于± 5% ,用t检验法对两法测定结果差别进行显著性检验 ,两法所得结果差别无显著意义 .紫外分光光度法可成为一种表征含甲基丙烯酰氧端基大分子单体数均分子量的方便方法 .     

聚醚砜单烯大分子单体的合成与表征及其共聚物的光学特性

本文采用溶液法以单酚（４－氯－４’－羟基二苯砜）为原料合成了不同聚合度的单酚低聚体，得到了控制聚合度的最佳聚合条件；用相转移催化剂法成功地将单酚转化为单烯大分子单体，并用ＩＲ、１Ｈ—ＮＭＲ对其结构进行了表征；测定了双键官能度均在１．９０以上．单烯大分子单体与苯乙烯的共聚研究表明，聚合度为２左右的单烯大单体在苯乙烯中溶解度最大，可达８０％以上；共聚物有优异的光学特性，对折射率的提高比相应的双烯大分子单体有利；在可见及近红外区透光率达８９％以上．     

New polymer syntheses. LXXXII. Syntheses of poly(ether-sulfone)s from silylated aliphatic diols including chiral monomers

Attempts were made to synthesize poly(ether-sulfone)s from aliphatic diols or bissilylated diols on the one hand, and 4,4′-dichlorodiphenylsulfone or 4,4′-difluorodiphenylsulfone on the other hand. The reaction conditions and the catalyst were varied. Polycondensations of silylated diols with 4,4′-difluorodiphenylsulfone and powdered K₂ CO₃ in N-methylpyr-rolidone proved to give the best results. Using silylated isosorbide and isomannide as mono-mers chiral poly(ether-sulfone)s were prepared. GPC measurements indicate weight-average molecular weights in the range of 27×10³–200×10³. © 1995 John Wiley & Sons, Inc.     

高效液相色谱对聚醚砜低聚物及其单体组分的分离与测定

In this work, the condition for the analysis of title compounds by HPLC was chosen.The componentcontent and average molecular weight of some kinds of poly(ether-sulfone)s oligomers were determined suc-cessfully. The optimum condition for the partial hydrolysis reaction from 4,4'-dichlorodiphenylsulfone to 4-chloro-4'-hydroxyldiphenylsulfone was obtained.In addition,the constituent changes of the oligomer can beobserved and determined by this method in the polymerization process.     

A facile synthesis of hydrophilic poly(ε-caprolactone)-based poly(ether-ester-amide)s

Segmented poly(ether-ester-amide)s, (PEEA)s, of controlled hydrophilicity degree, based on poly(ε-caprolactone) (PCL), were synthesized according to a facile two-step procedure using α,ω-dihydroxy oligomeric PCL, 4,7,10-trioxa-1,13-tridecanediamine and macromers prepared from poly(ethylene glycol)s and adipoyl chloride. The PEEAs showed M _n values in the range 5–11.5 kDa. A PCL-type crystallinity was found by WAXS. DSC indicated T_m values (49–51 °C) close to that of PCL macromer. Single glass transitions were observed both by DSC and DMTA techniques and the T_g values (−58–−50 °C by DSC) were slightly higher than that of PCL. The water uptake was in the range 4.8–26.0 wt.-% depending on the length of the poly(ethylene glycol) segment.

Monomers used to prepare the PEEAs.     

Model studies on the structure of poly(amide oxime)s and their cyclodehydration reactions leading to poly(1,2,4-oxadiazole)s

To obtain an understanding of the low molecular weight character of wholly aromatic poly(1,4-arylene acyldiamide oxime)s (PAAs) having n-alkyloxymethyl side braches and the additional decrease in molecular weight during their cyclodehydration reaction leading to the corresponding poly(1,4-arylene-1,2,4-oxadiazole)s (PAOs), tautomeric structures of poly[1,4-phenylene-2,5-bis(n-octyloxymethyl)terephthaldiamide oxime] (C₈-PAA) were ¹H-NMR-spectroscopically investigated by using two model compounds: O,O'-dibenzoyl terephthaldiamide oxime (H-PAA-M, 4) and O,O'-dibenzoyl-2,5-bis(n-octyloxymethyl) terephthaldiamide oxime (C₈-PAA-M, 5). In solution H-PAA-M existed exclusively as oximino isomer, while C₈-PAA-M consisted only of imino tautomer and C₈-PAA contained both the oximino and imino form, the former being dominant in composition. It was found that the presence of imino tautomer caused serious effects both on the low molecular weight character of C₈-PAA and on the additional decrease in molecular weight during thermal cyclodehydration to C₈-PAO, whereas the presence of oximino tautomer showed practically little effect. A discussion on the results is provided from mechanistic viewpoint. © 1993 John Wiley & Sons, Inc.     

Synthesis and characterization of phthalazinone containing poly(arylene ether)s via a novel N–C coupling reaction

High‐molecular‐weight poly(phthalazinone)s with very high glass‐transition temperatures (T_g's) were synthesized via a novel N–C coupling reaction. New bisphthalazinone monomers ( 7a–e ) were synthesized from 2‐(4‐chlorobenzoyl) phthalic acid in two steps. Poly(phthalazinone)s, having inherent viscosities in the range of 0.34–0.91 dL/g, were prepared by the reaction of the bis(phthalazinone) monomers with an activated aryl halide in a dipolar aprotic solvent in the presence of potassium carbonate. The poly(phthalazinone)s exhibited T_g's greater than 230 °C. polymer 8b synthesized from diphenyl biphenol and bis(4‐flurophenyl) sulfone demonstrated the highest T_g of 297 °C. Thermal stabilities of the poly(phthalazinone)s were determined by thermogravimetric analysis. All the poly(phthalazinone)s showed a similar pattern of decomposition with no weight loss below 450 °C in nitrogen. The temperatures of 5% weight loss were observed to be about 500 °C. The poly(phthalazinone)s containing 4,4′‐isopropylidenediphenol and 4,4′‐(hexafluoroisopropylidene) diphenol and diphenyl ether linkage were soluble in chlorinated solvents such as chloroform. Other poly‐(phthalazinone)s were soluble in dipolar aprotic solvents such as N,N′‐dimethylacetamide. The soluble poly(phthalazinone)s can be cast as flexible films from solution. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2481–2490, 2003     

New rigid-rod poly(benzoxazole-imide)s containing chloro-substituted p-phenylene units in the main chain

A series of new poly(o-hydroxy amide-imide)s with high molecular weights were synthesized by low-temperature solution polycondensation from a preformed imide ring and chloro- or dichloro-substituted p-phenylene-containing diacid chlorides of 2,5-bis(trimellitimido)chlorobenzene or 1,4-bis(trimellitimido)-2,5-dichlorobenzene and three bis(o-amino phenol)s. All the poly(o-hydroxy amide-imide)s were readily soluble in a variety of organic solvents such as N-methyl-2-pyrrolidone and N,N-dimethylacetamide. Transparent and flexible films of these polymers were cast from their solutions. The cast films had tensile strengths ranging from 88 to 102 MPa and elongations at break of 8–12%. Subsequent thermal cyclodehydration of the poly(o-hydroxy amide-imide)s afforded novel poly(benzoxazole-imide)s. The poly(benzoxazole-imide)s exhibited glass-transition temperatures in the range of 310–338 °C and were stable up to 500 °C in nitrogen, with 10% weight-loss temperatures recorded between 550 and 570 °C in nitrogen. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4151–4158, 1999     

Comparative Thermogravimetric Studies of Poly(ether-ketone/sulfone) Imides and Their Parent Polymers: I. Poly(ether-ketone/sulfone) ethylimide

Thermogravimetry (TG) was employed to study the thermal degradation kinetics of poly(etherketone/sulfone)ethylimide (PEK-IE and PES-IE). The corresponding decomposition activation energies and reaction orders were obtained and the comparison was made with their parent polymerspoly(ether-ketone/sulfone) with Cardo group (PEK-C and PES-C). The results show that the degradation activation energies of PEK-IE and PES-IE were lower than that of PEK-C and PES-C; and two stages of the degradation process were found for all the four polymers. For PEK-IE and PES-IE, the activation energies in the first decomposition stage are much lower than that in the second stage and the two stages can be taken as slow induction and fast degradation, whereas for PEK-C and PES-C the activation energies in the first decomposition stage are larger than that in the second stage, and the two stages can both be taken as two fast degradation stages. The decomposition mechanism of the two stages was also speculated.This revised version was published online in November 2005 with corrections to the Cover Date.     

Synthesis of high molecular weight poly(ether ketone)s by polycondensation of activated bis(aryl chloride)s with bisphenolates

The ability to achieve high molecular weight poly(ether ketone)s from the polycondensation of bis(aryl chloride)s with bis(phenolate)s has been consistently demonstrated. The polymerizations presented here help to delineate for specific bis(aryl chloride)/bisphenolate pairs the reaction conditions required to obtain high molecular weight polymers. Polycondensation of 1,3-bis(4-chlorobenzoyl)-5-tert-butylbenzene ( 6 ) and 2,2′-bis(4-chlorobenzoyl)-biphenyl ( 15 ) with various bisphenolates as well as of 2,2′-bis(4-hydroxyphenoxy)biphenyl ( 33 ) with 4,4′-dichlorobenzophenone ( 41 ) and 1,3-bis(4-chlorobenzoyl)benzene ( 43 ) were used as representative model systems to select reaction conditions that led to high molecular weight polymers. © 1995 John Wiley & Sons, Inc.     

Synthesis of highly fluorescent materials: Isoindole-containing polymers

A series of stable, highly fluorescent and highly phenylated isoindoles have been synthesized by treating the respective o-dibenzoylbenzenes with anilines at 200°C in the presence of a catalytic amount of p-toluenesulfonic acid. The correlation between the emission frequences and the structures of the isoindoles is described. The same reaction has also been used to transform a series of poly(o-dibenzoylbenzene)s into poly(isoindole)s. The resulting polymers have been studied by ¹H-NMR, DSC, TGA, and fluorescence spectra. They are highly fluorescent materials with high molecular weights, high glass transition temperatures, and high thermal stabilities. The tetraphenyl substituted isoindole-containing polymers have a maximum emission around 468 nm, whereas the diphenyl substituted isoindole-containing polymers have their maximum emission around 486 nm. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 3293–3299, 1999