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1.
合成了具有含不同量聚四亚甲基醚二醇(PTMG)的PTMG-PLA嵌段共聚物,并以IR,GPC,′H-NMR,和DSC进行了表征。通过应力-应变曲线研究了共聚物的力学性能。结果表明,共聚物的GPC曲线上只出现单一的流出体积峰,分子量分布多分散系数(?)_n/(?)_n小于2.0;另外,共聚物的T_g随其中的PTMG含量增加而降低,断裂伸长率随共聚物中PTMG含量的增加而增大,而应力,模量等力学性能则随共聚物中PTMG含量增加而降低。共聚物的体外降解速度较PLA均聚物的降解速度平缓。  相似文献   

2.
黄河  张辽云  李化毅  胡友良 《催化学报》2010,26(8):1077-1082
 以三乙基铝 (TEA) 为保护剂, 研究了 TiCl4/MgCl2/芴二醚/Al(C2H5)3 体系催化丙烯与十一烯醇或十一烯酸的共聚反应. 结果表明, 在极性单体存在下, 聚合反应活性随极性单体加入量的增加而降低, 但可保持丙烯均聚活性的一半以上, 反应活性衰减较小. 同时, 随着极性单体加入量的增加, 极性单体在共聚物中的含量增加. 与十一烯酸相比, 十一烯醇共聚具有更高的共聚活性和共单体含量. 随着共聚物中极性单体含量的增加, 聚合物的熔点和结晶温度都有所降低. 反应温度对丙烯和十一烯醇共聚的反应活性和共单体含量影响较小.  相似文献   

3.
王湘  叶霖  张爱英  冯增国 《应用化学》2010,27(4):413-417
由甲基丙烯酸正丁酯(BMA)与2-(2'-碘苯甲酰)-O-甲基丙烯酸乙酯(2-IEMA)自由基共聚制备了一种X光显影材料。1H NMR分析表明,该共聚物中2种结构单元之比与投料比吻合。GPC测得该共聚物的分子量随2-IEMA含量增加而降低。DSC分析表明,共聚物的玻璃化转变温度在22.3~28.0 ℃之间,与Fox方程计算值比较接近,而且随2-IEMA含量的增加而升高。TGA测得共聚物的分解温度为250 ℃,具有很好的热稳定性。力学性能测试结果表明,共聚物的拉伸强度随BMA含量的增加而增加,最大拉伸强度可达到7.46 MPa。X光显影性测试表明,该共聚物具有良好的显影性,显影效果随2-IEMA含量增加而增强。  相似文献   

4.
以丙烯腈(AN)、甲基丙烯酸甲酯(MMA)、丙烯醛(A)为单体,采用乳液聚合法制成一种共聚物———聚(丙烯腈 甲基丙烯酸甲酯 丙烯醛) (PAMA) .将PAMA作为第二共聚物与聚(偏氟乙烯 六氟丙烯) (PVDF -HFP)共混,并向反应体系中添加纳米级SiO2 ,充分混合后利用二次相转移法制得薄膜,并对所得薄膜的断面形貌、吸附性能、热性能、导电性能等进行了测试.研究发现,SiO2 的加入增大了膜中微孔体积,改善了微孔分布,且增大了电解液的吸附量;共聚物PAMA的组成影响薄膜的吸附性能,其中极性较大的丙烯醛单元和丙烯腈单元起着决定性作用;PAMA含量的增加使得共混膜吸附电解液量增加.制得共混膜的离子电导率达2 . 30×10 - 3S cm .  相似文献   

5.
采用商业聚(偏氟乙烯-co-三氟氯乙烯)(P(VDF-co-CTFE)为原料,结合氢化反应、ATRP和磺化反应系统合成了一系列聚(偏氟乙烯-co-三氟乙烯-co-三氟氯乙烯)-g-磺化聚苯乙烯(P(VDF-co-TrFE-co-CTFE)-g-SPS)共聚物.重点研究了测试环境(如温度和相对湿度)、聚合物微观结构(接枝密度,接枝长度等)对聚合物形貌、吸水率和质子传导率的影响.研究表明,在接枝量相同的情况下,随着接枝密度的降低,聚合物的相分离更加明显,亲水相从孤岛型逐渐转变为部分连续型;聚合物的吸水率随磺酸基摩尔含量增加而提高;聚合物的质子传导率随着温度的提高和湿度的降低而降低;在较低温度下,聚合物的电导率随接枝密度的增加而降低,而在较高温度下,聚合物的电导率随接枝密度的增加而升高.组成优化的P(VDF-co-TrFE-co-CTFE)-g-SPS共聚物在30~120℃和高湿度条件下,其质子传导率明显优于Nafion112膜.  相似文献   

6.
采用溶液混合法制备了聚 [(双 甘氨酸乙酯 )膦腈 ](PGP)与聚酸酐 (PSA或PSTP)的共聚物 .利用示差扫描量热仪和相差显微镜研究了两体系的共混相容性 ,发现PGP与PSTP具有部分相容性 .体外降解试验表明 ,PGP PSTP降解行为呈均一性 ,且由于PSTP酸性产物的催化作用 ,降解速度明显较PGP加快 (约 15天 )并随PSTP含量增加而加快 .PGP PSTP有望成为一种新型的药物控释载体材料  相似文献   

7.
丙烯酸十八酯共聚物的结晶和熔融行为研究   总被引:1,自引:0,他引:1  
合成了丙烯酸酯(AAn,n为侧链碳原子数)均聚物(PAAn)以及AA18与其同系物的无规共聚物((P(AA18-co-AAn)),并研究了P(AA18-co-AAn)的结晶和熔融行为.结果表明,在AA18与结晶同系物AAn(n=10,12,14,16)的共聚物中,结晶度(Xc)随AA18含量的增加而增大,相应的熔程先增加后下降,存在一个最大值;P(AA18-co-AA14)和P(AA18-co-AA16)的相对结晶度(Xc/Xcmax)受AA18含量影响不大,而P(AA18-co-AA10)和P(AA18-co-AA12)的Xc/Xcmax随AA18含量增加先下降后上升;随着AA18与共聚组份侧链碳原子数差别的增大,熔程的最大值明显增加.在AA18与非结晶同系物AAn(n=4,6,8)的共聚物中,Xc和Xc/Xcmax值随AA18含量的增加而增大,而Xc/Xcmax值随AAn侧链碳原子数的增加而减少,共聚物熔程的最大值差别不大.  相似文献   

8.
化学交联聚氯乙烯树脂的合成和结构   总被引:2,自引:0,他引:2  
研究了氯乙烯/交联单体悬浮共聚时,交联单体种类、浓度和聚合温度对化学交联聚氯乙烯树脂结构的影响.对于氯乙烯/邻苯二甲酸二烯丙基酯(VC/DAP)悬浮共聚体系,凝胶含量和凝胶交联密度随DAP起始浓度的增加而增大;DAP浓度相同时,凝胶含量和凝胶交联密度随聚合温度上升而下降;当凝胶含量较高时,分子链物理缠结对凝胶交联密度有较大贡献,凝胶交联密度随凝胶含量增加而快速上升.在相同交联单体浓度下,氯乙烯/马来酸二烯丙基酯(VC/DAM)共聚物的凝胶含量最大,VC/DAP共聚物次之,氯乙烯/乙二醇二甲基丙烯酸酯(VC/EGDMA)共聚物最小,这是由于DAM单体的竞聚率小于1,且含有马来酸双键,EGDMA单体的竞聚率远大于1.  相似文献   

9.
研究了交替马来酸酐共聚物多缩乙二醇酯(CP350)-LiNO3络合物的热行为及离子导电性。实验表明:CP350/LiNO3络合物在所研究的[Li]/[EO]配比范围呈均相无定形并具有二重玻璃化转变。2个玻璃化转变温度均随盐含量的增加而上升。离子电导率随盐浓度的变化出现1个极大值,室温电导率最大可达3.72×10-5S/cm.导电行为呈典型VTF特征。  相似文献   

10.
以双硫酯为链转移剂的活性自由基聚合   总被引:6,自引:0,他引:6  
合成并研究了两种双硫酯链转移剂的纯化方法 ,进行了多种单体以双硫酯为链转移剂的活性自由基聚合及嵌段共聚 .发现以PhC(S)SC(CH3) 2 Ph为链转移剂的效果比PhC(S)SCH(CH3)Ph好 ,聚合产物的多分散性系数较小 .引发剂与链转移剂的摩尔数比为 1∶3 5~ 1∶4 2时 ,得到多分散性系数小 ,实测分子量与理论分子量相近的聚合产物 .聚合物的分子量随时间和转化率的增加而增加 ,加入第二单体形成嵌段共聚物 ,具有活性聚合特征 .聚甲基丙烯酸酯大分子引发剂引发丙烯酸酯单体聚合时 ,聚合速度最快 .  相似文献   

11.
Ethylene–vinyl alcohol copolymers, EVOH, with two different vinyl alcohol compositions have been functionalized with carboxylic acid groups by reaction with phthalic anhydride. Later on, the coupling reaction of three aminosaccharides (D ‐(+)‐glucosamine, D ‐(+)‐galactosamine, and D ‐(+)‐mannosamine) to functionalized EVOH copolymers has been carried out in dimethyl sulfoxide at 70 °C to achieve water soluble glycopolymers. The structure of the resulting functionalized copolymers and the new glycopolymers was confirmed by 1H and 13C NMR. Likewise, the thermal behavior of glycopolymers has been performed by differential scanning calorimetry and thermal gravimetric analysis. In addition, their affinity to lectins, specifically to Concanavalin A and Ricinus Communis Agglutinin, has been evaluated. © Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7238–7248, 2008  相似文献   

12.
Viscometry was used to follow the epoxidation of polybutadiene and styrene–butadiene triblock copolymers (SBS) with monoperoxyphthalic acid (MPPA). Long reaction periods lead to an abnormal increase and then drop in reduced viscosity. The increasing viscosity is due to repulsion between oxirane group and its ring-opening product with phthalic acid, while the viscosity drop can be correlated with a decrease of molecular weight. Long-term storage of the epoxidized polyenes in the reaction solution containing phthalic acid, which is the derived product from MPPA, also leads to the dramatic decrease in molecular weights. The occurrence of degradation was confirmed by GPC analysis of molecular weight and molecular weight distribution. Chloroform accelerated the degradation reaction, possibly through the generation of hydrochloric acid. The degraded products were isolated and analyzed by GPC and NMR. A free radical mechanism was proposed for the oxidative degradation of epoxidized polyenes after excessive reaction.  相似文献   

13.
Glycopolymers based on the incorporation of a diaminobutylmaltotrionolactone onto activated ethylene‐vinyl alcohol, EVOH, copolymers with distinct composition in the former counit have been prepared. Previous transformation of initial hydroxyl EVOH groups to other more reactive functional groups has been required. The activation has been performed in this current investigation by functionalization with either 4‐nitrophenyl carbonate or o‐phthalic acid groups. The structure of the resulting novel water‐soluble glycopolymers has been confirmed by FTIR, 1H and 13C‐NMR spectroscopies. In addition, the glass transition temperatures and thermal stability as well as the viscoelastic behavior in bulk and in water solution have been examined as a function of chemical linkage nature. The rheological evaluation confirms the reversible gel formation in all the cases. Finally, their affinity to Concanavalin A lectin has been also analyzed proving the feasible use of these glycopolymers as molecular recognition materials. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 719–729, 2010  相似文献   

14.
The thermal degradation of copolymers based on butyl acrylate-methyl acrylate-acrylic acid used as acrylic pressure-sensitive adhesives, especially for bonding of plasticizer containing materials, has been investigated using thermogravimetry and pyrolysis-gas chromatography at 250°C. It was observed that during the pyrolysis of butyl acrylate-methyl acrylate-acrylic acid copolymers unsaturated monomers as methyl acrylate, methyl methacrylate, butyl acrylate and butyl methacrylate were formed. During the side-chain butyl acrylate-methyl-acrylate-acrylic acid-copolymer degradation the presence of methyl alcohol and butyl alcohol was observed.  相似文献   

15.
荧光法快速测定邻苯二甲酸酯的总量   总被引:1,自引:0,他引:1  
基于邻苯二甲酸酯在浓硫酸下荧光增强的原理构建了一种测定邻苯二甲酸酯总量的荧光分析新方法。 体系的荧光强度与邻苯二甲酸酯的浓度在5.00~600 μg/L的范围内呈线性关系,方法的检出限为0.57 μg/L,回收率在91.6%~105.1%之间。 该方法简单、快速、灵敏度高、线性范围宽。 用于塑料水杯和聚氯乙烯水管中邻苯二甲酸酯总量的测定,结果令人满意。  相似文献   

16.
The bulk copolymerizations of monoallyl phthalate (MAP) with allyl benzoate (ABz) and diallyl phthalate (DAP) were conducted in the presence of benzoyl peroxide as an initiator at 70°C; copolymers containing allyl alcohol unit were obtained. The copolymer composition was reasonably interpreted in terms of polymerization kinetics, including the partial elimination of phthalic anhydride (PhA) from the MAP growing chain end in its propagation reaction with another monomer. Kinetics of the copolymerization of DAP with MAP were also discussed in detail, and the gel point was additionally evaluated. DAP–MAP copolymer was homogeneously reacted with zinc acetate to produce the polymer gel carrying ionic crosslinkages.  相似文献   

17.
袁冰  张新  侯万国 《化学研究》2010,21(6):45-48
以对苯二甲酸根阴离子为预支撑体,制备了磷钨酸插层Zn/Al类水滑石杂化物催化剂,将其用于邻苯二甲酸二(2-乙基)己酯(DOP)的合成反应.研究了原料配比、催化剂用量、反应温度、反应时间等对邻苯二甲酸酐转化率的影响,及催化剂的可重复利用性.结果表明,磷钨酸-Zn/Al类水滑石杂化催化剂对DOP合成的催化效果较好,在催化剂用量为苯酐质量的0.76%,异辛醇与邻苯二甲酸酐的摩尔比为2.5,反应温度为180℃,反应时间为4.5 h,带水剂环己烷约为苯酐质量65%的反应条件下,苯酐转化率可达92.8%;反应10 h转化率可达97.9%.催化剂重复使用时转化率略有下降,经过乙醇洗涤再生,活性即可基本恢复.  相似文献   

18.
Novel glycopolymers have been prepared from ethylene–vinyl alcohol copolymers, EVOH. For that purpose, three distinct aminosaccharides (N-(4-aminobutyl)-d-gluconamide (NABG), N-(4-aminobutyl)-O-β-d-galactopyranosyl-(1 → 4)-d-gluconamide (NABL) and N-(4-aminobutyl)-O-β-d-glucopyranosyl-(1 → 4)-d-gluconamide (NABM) have been synthesized. The previous functionalization of these EVOH copolymers is mandatory to activate their hydroxyl reactivity before the subsequent coupling reaction with the aminosaccharides. The activation with carboxylic acid groups by reaction with phthalic anhydride has been chosen in the current investigation because of its almost quantitative yield and the subsequent high modification extent reached (>60%). The glycopolymers that turned out water-soluble (i.e., those based on NABL and NABM) have shown a reversible network formation unusually described in glycopolymers. In addition, their capability to interact with lectins, particularly Concanavalin A and Ricinus communis Agglutinin, has confirmed the specificity of lectin recognition in these glycopolymers.  相似文献   

19.
A procedure was developed for the simultaneous determination of phthalic acid isomers; the procedure includes the preparation of diisoamyl esters by reaction with isoamyl alcohol in a benzene solution in the presence of sulfuric acid with the distillation of an azeotrope mixture of benzene with water, the neutralization of acid with triethylamine, and the separation of esters by gas-liquid chromatography on a steel column (1 m × 3 mm) filled with Chromaton N-AW-HMDS with 5% Apiezon L in the temperature programming mode with flame-ionization detection. The time of separation is 13 min. The time of the sample preparation step is 2–2.5 h. The lower determination limit is 20 ng. The procedure allows the determination of phthalic acids in the concentration range from 0.02 to 2 mg/L in liquid samples and from 0.03 to 3 mg/m3 in air.  相似文献   

20.
This study presents the synthesis of polyesters obtained from phthalic anhydride as acidic components and one mixture of monoethylene glycol and monohydric alcohol (in ratio 1.1:0.15). Molar ratio of the acid component and alcohol component was 1:1.25. n-Propanol, n-butanol, n-octanol and isoamyl alcohol were used as monohydric alcohol. Physicochemical characterization was performed by elemental analysis, FTIR/UATR spectroscopy of polyesters and char, EGA (evolved gas analysis), thermal analysis in synthetic air and in nitrogen atmosphere.  相似文献   

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