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1.
测定了丙烯酰胺与4-乙烯基吡啶共聚反应的竞聚率。用紫外分光光度法测定了不同浓度的4-乙烯基吡啶均聚物的吸光度,从而求出在低转化率不同初始单体组成的共聚物中4-乙烯基吡啶含量。用FR和KT两种作图法及YBR计算法对单体的竞聚率进行计算和比较。结果表明:KT法和YBR法计算法较为准确,4-乙烯基吡啶的竞聚率和丙烯酰胺的竞聚率分别为γrVP=0.636,γAM=0.379。  相似文献   

2.
采用核磁共振氢谱, 研究了N-苯基马来酰亚胺(NPMI)与对氯甲基苯乙烯(PCMS)在氘代氯仿中的络合性能. 以PCMS作为引发剂单体, 通过原子转移自由基聚合(ATRP)引发NPMI-PCMS电子转移络合物(CTC)进行活性可控超支化共聚合. 考察了单体初始摩尔分数对共聚物组成和其玻璃化转变温度的影响, 用Kelen-Tudos法计算得到两种单体的竞聚率分别为 rNPMI=0.11和rPCMS=0.25. 结果表明, 当单体配比fNPMI=0.4~0.7时, 共聚物具有交替结构, 其耐热性随着NPMI含量的增加而提高. 此外还考察了溶剂、聚合温度等对共聚合反应动力学的影响. 并进一步用所得超支化交替共聚物作为大分子引发剂, 引发甲基丙烯酸甲酯(MMA)聚合, 制得了多臂超支化接枝共聚物 poly(NPMI-co-PCMS)/poly(MMA).  相似文献   

3.
以烯丙醇聚氧乙烯醚(APEG)和马来酸酐(MA)为单体,过硫酸钾(K2S2O8)为引发剂,蒸馏水为溶剂,在65℃下,自由基聚合合成共聚物P(APEG-co-MA)。利用凝胶渗透色谱仪对聚合物进行表征,计算得烯丙醇聚氧乙烯醚与马来酸酐共聚物的组成摩尔比,得到的实验数据利用FR法、KT法和YBR法进行竞聚率的计算。结果表明,在低转化率的条件下,烯丙醇聚氧乙烯醚与马来酸酐的竞聚率分别为r1=0.33090,r2=0.04761,说明与马来酸酐相比,烯丙醇聚氧乙烯醚更易倾向自聚,马来酸酐基本不发生自聚。  相似文献   

4.
采用溶液聚合制备了新型阳离子共聚物--聚丙烯酰胺基-丙烯酰氧乙基三甲基氯化铵(P(AM-DAC)),采用滴定法测定了其阳离子共聚物的阳离子度.分别采用Fineman-Ross 法、Kelen-Tudos 法和Yezrielev-Brokhina-Roskin法计算出单体竞聚率.结果表明,KT法和YBR法计算较为准确,丙烯酰氧乙基三甲基氯化铵和丙烯酰胺的竞聚率分别为rDAC=0.383 5,rAM=2.286 4.  相似文献   

5.
本文采用红外光谱技术测定了共聚物的组成,用最小二乘曲线拟合法计算了甲基丙烯酸三甲基锡酯(TMTM),三乙基锡酯(TETM),三丁基锡酯(TBTM),和三苯基锡酯(TPTM)与甲基丙烯酸甲酯(MMA)的共聚合竞聚率,其数值分别为:r_1=1.07,r_2=0.63(TMTM/MMA);0.87,0.62(TETM/MMA);0.62,0.58(TBTM/MMA);0.68,0.60(TPTM/MMA),并计算了各单体的δ和e值,讨论了不同取代基结构对其共聚合相对活性的影响。  相似文献   

6.
本文研究了苯乙烯(St,M1)与N、N-二甲胺基甲基丙烯酸乙酯(MAEMA,M2)以AIBN为引发剂,在丁酮溶液中的共聚合反应。用元素分析法测定了共聚物的组成,同时分别用FR法、YBR法和K-T法对单体竞聚率进行估价。结果表明三种计算方法得到的单体竞聚率基本一致,结果分别为r1=0.510,r2=0.716(FR法);r1=0.512,r2=0.720(YBR法);r1=0.505,r2=0.697(K-T法)。  相似文献   

7.
丙烯酸β-羟丙酯与苯乙烯共聚合的研究   总被引:1,自引:0,他引:1  
<正> 丙烯酸β-羟丙酯(HPA) 是一种具有多种反应功能的丙烯酸酯类单体,由它制得的大分子同时带有羰基、酯基和羟基,因而可用它制备特定功能的大分子如耐火树脂、涂料、油田助剂及水处理剂等,国内外对HPA的共聚合活性报道很少,CHOW曾研究过HPA与苯乙烯(St)的共聚合,并用Mayo-Lewis方程法计算出它们的竞聚率。本文研究了HPA与St在甲苯溶液中的自由基共聚合,用Mayo-Lewis方程法、FR法、YBR法及K-T法四种方法分别计算出St-HPA共聚合出竞聚率r_1、r_2及HPA的Q、e值,作出了共聚物组成曲线,并由此计算出St-HPA共聚物的平均序列长度及序列长度分布。  相似文献   

8.
以传统Ziegler-Natta催化体系TiCl4/Al(#em/em#-Bu)3催化降冰片烯(NBE)和异戊二烯(IP)的共聚合, 制得可溶于常规有机溶剂的共聚物, 其数均分子量为2.0 × 104~6.5 × 104, 分子量分布指数为1.5~2.9, 降冰片烯结构摩尔含量为26%~60%. 考察了助催化剂用量、 聚合温度及2种单体投料比对共聚合的影响. 结果表明, 当降冰片烯与异戊二烯的投料摩尔比为4∶6时, 于40 ℃聚合6 h, 得到的共聚物产率为96%, 数均分子量为6.5×104, 降冰片烯结构含量45%. 用 1H NMR, 13CNMR, GPC和DSC等方法表征了共聚产物的微观结构与热性能. 13C NMR DEPT结果表明, 共聚反应中降冰片烯单体以加成方式聚合. DSC结果显示, 共聚物只有一个玻璃化转变温度(Tg=20~40 ℃). 通过Kelen-Tüdös方法得到2种单体的竞聚率分别为rNBE=0.07, rIP=0.44.  相似文献   

9.
四氟乙烯/偏氟乙烯乳液共聚反应的竞聚率测定   总被引:3,自引:0,他引:3  
用亨利定律关联了四氟乙烯 (TFE) /偏氟乙烯 (VDF)乳液共聚合体系中的单体气相分压与其对应液相浓度间的关系 ,推导了用气相摩尔分数表示的共聚物组成方程式 .通过气相色谱和19F NMR分别测定了共聚反应前后气相单体组成和共聚物组成 ,用非线性回归法 (RREVM )计算TFE/VDF乳液共聚合反应表观竞聚率分别为γTFE=0 35和γVDF=0 6 3 .将实测的表观竞聚率代入共聚物组成方程计算共聚物组成与由19F NMR测定的结果一致 ,为进一步的工业放大试验提供科学依据  相似文献   

10.
含氟丙烯酸酯共聚物的合成与表征   总被引:2,自引:1,他引:1  
本文以丙烯酸丁酯(BA)和1,1,5-三氢全氟戊基丙烯酸酯 (OFPA)为主要单体,甲基丙烯酸缩水甘油酯(GMA)为活性单体,采用间歇式滴加乳液聚合法合成了含氟丙烯酸酯共聚物.采用红外光谱法和X-射线光电子能谱法对共聚物的结构进行了表征,对共聚物的凝胶含量、耐水、耐溶剂性能以及热性能进行了测试.结果表明共聚物具有良好的耐水和耐溶剂性能,共聚物中保持一定的凝胶率可降低其表面粘性,有利于后期混炼加工;DSC测得的共聚物的玻璃化转变温度可低于-30℃,保持了较好的低温性能.  相似文献   

11.
以醋酸乙烯酯(VAC)和甲基丙烯酸缩水甘油酯(GMA)为单体,甲基丙烯酸烯丙酯(AMA)为交联剂,在致孔剂正庚烷/乙酸丁酯的存在下,悬浮聚合,制得了一系列大孔共聚物;醇解后得到一种新型聚乙烯醇系亲和层析基质。依据单体的Q、e值,计算了体系的竞聚率,讨论了不同交联度、GMA含量、致孔剂用量及配比对基质孔结构和性能的影响。  相似文献   

12.
Colloidal polystyrene particles with surface epoxy groups have been synthesized through surfactant-free emulsion copolymerization of styrene with glycidyl methacrylate; and through copolymerization of glycidyl methacrylate (GMA) and methyl methacrylate as shells around existing polystyrene seed particles. We developed two titration methods to quantify the number of epoxy groups that survived the polymerization processes. The styrene-GMA copolymer particles were judged to be unsatisfactory as model colloidal materials due to their size polydispersity and unknown internal distribution of epoxy groups. The core-shell particles had high epoxy surface densities with at least 60% of the initial epoxy groups surviving the synthesis process. Transmission electron microscopy shows that the thickness of the epoxy-rich shell is less than expected based on the volume of monomers added, suggesting that some of the monomer forms water-soluble oligomers. Photon correlation spectroscopy measurements imply that the shell is swollen with water and consists of polymer configurations which extend out into solution. The morphological details vary consistently with the GMA content, and hence the hydrophilicity, of the shell polymer. © 1995 John Wiley & Sons, Inc.  相似文献   

13.
甲基丙烯酸甲酯-丙烯酸丁酯共聚物微观结构研究   总被引:3,自引:0,他引:3  
用13C NMR研究了由基团转移共聚得到的甲基丙烯酸甲酯 丙烯酸丁酯共聚物的微观结构,共聚物中单体链节的三元组含量从季碳和羰碳的共振信号测得,实验测得的三元组分数与通过竞聚率和单体组成比按末端基效应模式的计算值相符.丙烯酸丁酯由于具有大得多的竞聚率值而呈现较强的均聚倾向.  相似文献   

14.
A two‐step synthetic route to novel copolymer networks, consisting of polymethacrylate and polyacetal components, was developed by combining the polyaddition and anionic polymerization techniques. The functional polymethacrylates containing hydroxyl or vinyloxyl side groups were used as crosslinkers. They were anionically synthesized as follows: the copolymer of 2‐hydroxyethyl methacrylate (HEMA) and methyl methacrylate (MMA) was prepared by the anionic copolymerization of 2‐(trimethylsiloxy)ethyl methacrylate and MMA, followed by hydrolysis. The copolymer poly(HEMA‐co‐MMA) thus obtained possessed a hydroxyl group in each of its HEMA units. Another kind of vinyloxyl‐containing (co)polymer was prepared by the anionic homopolymerization of 2‐(vinyloxy)ethyl methacrylate (VEMA) or its copolymerization with MMA. The resulting (co)polymer possessed reactive vinyloxyl side groups. The copolymer networks were obtained by reacting each of the above‐mentioned (co)polymers with a polyacetal prepared via the polyaddition between a divinyl ether and a diol. Three divinyl ethers (ethylene glycol divinyl ether, 1,4‐butanediol divinyl ether, and 1,6‐hexanediol divinyl ether) and three diols (ethylene glycol, 1,4‐butanediol, and 1,6‐hexanediol) were employed as monomers in the polyaddition step, and their combinations generated nine kinds of polyacetals. When a polyaddition reaction was terminated with a divinyl ether monomer, a polyacetal with two vinyloxyl end groups was obtained, which could further react with the hydroxyl groups of poly(HEMA‐co‐MMA) to generate a copolymer network. On the other hand, when a diol was used as terminator in the polyaddition, the resulting polyacetal possessed two hydroxyl end groups, which could react with the vinyloxyl groups of poly(VEMA) or poly(VEMA‐co‐MMA), to generate a copolymer network. All the copolymer networks exhibited degradation in the presence of acids. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 117–126, 2001  相似文献   

15.
采用自由基引发剂对甲基丙烯酸三丁基锡酯和丙烯酸酯进行共聚合 ,其竞聚率用YBR法解出共聚方程的微分式而求得。甲基丙烯酸三丁基锡酯 (M1 )和丙烯酸甲酯 (M2 )、丙烯酸乙酯 (M2 )、丙烯酸丁酯 (M2 )共聚反应的竞聚率分别为r1 =1 .0 1± 0 .0 6, r2 =0 .2 9± 0 .0 3; r1 =1 .0 7± 0 .0 5 ,r2 =0 .38± 0 .0 3; r1 =1 .1 1± 0 .0 5 , r2 =0 .45± 0 .0 3; 而所得到的甲基丙烯酸三丁基锡酯的Q、e值是它对各个单体的所有Q、e值的平均值 ,其Q =0 .5 7,e=- 0 .39  相似文献   

16.
A successive method for preparing novel amphiphilic graft copolymers with a hydrophilic backbone and hydrophobic side chains was developed. An anionic copolymerization of two bifunctional monomers, namely, allyl methacrylate (AMA) and a small amount of glycidyl methacrylate (GMA), was carried out in tetrahydrofuran (THF) with 1,1‐diphenylhexyllithium (DPHL) as the initiator in the presence of LiCl ([LiCl]/[DPHL]0 = 2), at −50 °C. The copolymer poly(AMA‐co‐GMA) thus obtained possessed a controlled molecular weight and a narrow molecular weight distribution (Mw /Mn = 1.08–1.17). Without termination and polymer separation, a coupling reaction between the epoxy groups of this copolymer and anionic living polystyrene [poly(St)] at −40 °C generated a graft copolymer with a poly(AMA‐co‐GMA) backbone and poly(St) side chains. This graft copolymer was free of its precursors, and its molecular weight as well as its composition could be well controlled. To the completed coupling reaction solution, a THF solution of 9‐borabicyclo[3.3.1]nonane was added, and this was followed by the addition of sodium hydroxide and hydrogen peroxide. This hydroboration changed the AMA units of the backbone to 3‐hydroxypropyl methacrylate, and an amphiphilic graft copolymer with a hydrophilic poly(3‐hydroxypropyl methacrylate) backbone and hydrophobic poly(St) side chains was obtained. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1195–1202, 2000  相似文献   

17.
以醋酸乙烯酯(VAc)和甲基丙烯酸甲酯(MMA)为单体, 采用半连续种子乳液聚合法制备了无规共聚物聚(醋酸乙烯酯-甲基丙烯酸甲酯)[P(VAc-MMA)], 并以此聚合物为基体制备了聚合物电解质. 用红外光谱(FTIR)、核磁共振氢谱(1H NMR)、扫描电镜(SEM)、差热/热重分析(DSC/TG)、X射线衍射(XRD)、机械性能测试和电化学交流阻抗等方法对聚合物和聚合物电解质的性质进行了研究. 测试结果表明: VAc和MMA聚合生成P(VAc-MMA); 聚合物膜含有大量微孔结构, 利于离子传输; 聚合物电解质膜具有优良的热稳定性和机械强度; 25 ℃下, 最高的离子电导率达到了1.27× 10-3 S•cm-1; 离子电导率随着温度的升高而迅速增加, 电导率-温度曲线符合Arrhenius方程.  相似文献   

18.
A random copolymer P(VAc-MMA)was synthesized via seeded emulsion copolymerization with vinyl acetate (VAc)and methyl methacrylate(MMA)as monomers,and the polymer electrolytes comprising blend of corresponding copolymer P(VAc-MMA)as a host polymer and LiClO_4 as a dopant were prepared by solution casting technique. Performances of the synthesized copolymer and prepared polymer membrane and electrolyte were studied by FTIR,XRD, TG,DSC,mechanical testing and AC impedance.According to the study of FTIR and D...  相似文献   

19.
A tetrahydrofuran (THF) solution of the living random copolymer of methyl methacrylate (MMA) and glycidyl methacrylate (GMA) was prepared by the living anionic copolymerization of the two monomers, using 1,1‐diphenylhexyllithium (DPHLi) as initiator, in the presence of LiCl ([LiCl]/[DPHLi]0 = 3), at −50°C. The copolymer thus obtained has a controlled composition and molecular weight and a narrow molecular weight distribution. By introduction of an anionic living polystyrene (poly(St)) or anionic living polyisoprene (poly(Is)) solution into the above system at −30°C, a coupling reaction took place and a graft copolymer with a polar backbone and nonpolar side chains was produced. The solvent used in the preparation of the living poly(St) or poly(Is) affects the coupling reaction. When benzene was the solvent, a graft copolymer of high purity, controlled graft number and molecular weight, and narrow molecular weight distribution (Mw/Mn = 1.11–1.21) was obtained. In the coupling reaction, the living poly(St) reacted only with the epoxy groups and not with the carbonyls of the backbone polymer. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 105–112, 1999  相似文献   

20.
Divalent group 14 metal species, a germylene(la) and a stannylene(lb), behaved as a comonomer(reductant monomer) in the copolymerization with p-benzoquinone derivatives(oxidant monomer)(“oxidation-reduction copolymerization”) and as an initiator for anionic monomers. The copolymerization took place without initiator at a lower temperature to give an alternating copolymer. N-phenyl-p-quinoneimine also behaved as a reactive oxidant monomer toward la and lb. These species have been shown to induce the polymerization of anionically polymerizable monomers such as methyl methacrylate, methacrylonitrile, and 4-vinylpyridine. Based on the mechanistic examination of the polymerization, a new alternating copolymerization between la and 2-cyclohexene-l-one has been developed to produce a copolymer having a metal-enolate structure, which involves the oxidation-reduction process during the copolymerization.  相似文献   

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