水溶性线形-超支化嵌均共聚物合成及表征

采用三羟甲基丙烷三马来酸单酯（TMPTM）与甲基丙烯酸(MAA)在水中进行自由基共聚,合成线形-超支化嵌均聚合物(LHBPs)。单体竞聚率数值表明TMPTM与MAA之间为典型的嵌均共聚,NMR、 lg[η]-lgMw关系规律以及支化因子g’研究结果表明,当单体摩尔比n (MAA)/n(MTPTM)小于48时,产物显示超支化聚合物特征,当n (MAA)/n(MTPTM)≥48时,聚合物呈现线形聚合物特征。DSC分析表明,LHBP-3聚合物玻璃化转变温度约为209.98℃,TGA表明在50-600℃升温过程中,LHBP聚合物有两次分解,分解温度分别为206.38℃(脱羧)和429.57℃（骨架分解）。     

马来酸酯烯类支化单体合成及其与甲基丙烯酸的共聚

采用三羟甲基丙烷(TMP)和马来酸酐(MA)制备多官能度烯类支化单体单三羟甲基丙烷三马来酸单酯(MTPTM)。MTPTM与甲基丙烯酸(MAA)在水溶液中通过自由基聚合,制备超支化聚合物。采用NMR表征了MTPTM和超支化聚合物的结构。考察了MAA和MTPTM单体摩尔比对超支化聚合物相对分子质量、水溶液黏度、热稳定性以及玻璃化转变温度的影响。结果表明,随MAA单体用量增加,聚合物相对分子质量及其分布先降后升,n(MTPTM)∶n(MAA)=1∶9时出现最小值(Mw=2.09×104,Mw/Mn=1.66),产物水溶液黏度也呈现先降后升的趋势,并在n(MTPTM)∶n(MAA)=1∶6时出现最小值。而玻璃化转变温度则先升后降,n(MTPTM)∶n(MAA)=1∶9时出现最大值(Tg=274.5℃),MAA单体比例增加,有助于超支化聚合物热稳定性提高。     

交联剂TMPTMA的合成研究

对TMPTMA合成的工艺参数进行研究,结果表明,最佳工艺条件：MA／YMP=3．6／1（摩尔比）,HQ／TMP=0．19～0．26／1（摩尔比）,TSA/TMP=0．2／1（摩尔比）,溶剂用量为每摩尔TMP250～400mL,回流反应7～12h。按此工艺条件实验,能获得高收率、高含量的TMPTMA。     

轻度交联的支化嵌段共聚物POEGMA-b-PnBMA的合成

介绍了一种通过原子转移自由基聚合的方法一步合成两亲性支化嵌段共聚物的方法,并对其进行表征,测试了聚合物的核磁共振氢谱和粒度。     

1,1,1-三羟甲基丙烷三硝酸酯的合成与表征

以三羟甲基丙烷为原料,通过硝化反应,合成了1,1,1-三羟甲基丙烷三硝酸酯,研究了不同硝化剂对合成1,1,1-三羟甲基丙烷三硝酸酯的影响,找出了最佳添加剂和硝化剂。实验结果表明,当用98％硝酸作为硝化剂,三羟甲基丙烷与硝酸摩尔比为10：1,反应温度在0～20℃,反应时间为2h,1,1,1-三羟甲基丙烷三硝酸酯的收率可达99．7％,并用红外光谱、核磁共振、元素分析等对产品进行了表征。     

无规支化苯乙烯-甲基丙烯酸甲酯共聚物合成及表征

以α-溴代异丁酸叔丁酯(tBBiB)为引发剂,CuBr/2,2'-联吡啶(BPy)为催化体系,二乙烯基苯(DVB)为支化单体,经原子转移自由基聚合(ATRP),在90℃下进行了苯乙烯(St)和甲基丙烯酸甲酯(MMA)的共聚合反应,研究了不同单体组成对反应的影响.用红外光谱(FT-IR)、核磁共振氢谱(1H-NMR)、凝胶渗透色谱(GPC)、多角激光散射仪(MALLS)分别对聚合反应过程和聚合物进行了表征和分析.结果表明:反应表现出活性聚合特征,Mw.MALLS＞3.9×105;Mw.MALLS/Mw.GPC＞1,说明反应生成了St与MMA的无规支化共聚物:当St与MMA摩尔比为3∶1时,共聚物中St单元的含量最大.     

苯乙烯-甲基丙烯酸月桂酯-丙烯酸共聚物的合成及性能

以苯乙烯（St）、甲基丙烯酸月桂酯（LMA）、丙烯酸（AA）为单体,过氧化苯甲酸叔丁酯为引发剂,二丙二醇二甲醚为溶剂,采用自由基聚合方法,合成苯乙烯-甲基丙烯酸月桂酯-丙烯酸共聚物。考察了引发剂用量、单体摩尔配比、反应温度对聚合物性能的影响,并用红外光谱、差示扫描量热仪、凝胶色谱等对共聚物进行表征,结果表明,合成反应的最佳工艺条件是：n（St）：n（LMA）：n（AA）=5.7：0.3：4,过氧化苯甲酸叔丁酯用量为5%,反应温度为125℃,得到了多分散指数为1.67,具有良好成膜性的三元丙烯酸共聚物树脂。     

羟化含氟嵌段共聚物的合成

用α-溴代丙酸乙酯(EPN-B)/氯化亚铜(CuCl)/联二吡啶(bpy)作为ATRP催化引发体系,环己酮为溶剂,进行甲基丙烯酸2,2,2-三氟乙酯(TFEMA)的原子转移自由基聚合(ATRP),得到单分散PTFEMA-X预聚体。并以此预聚体为大分子引发剂引发甲基丙烯酸-β-羟乙酯聚合,得到分子质量可控、分子质量分布窄的聚甲基丙烯酸2,2,2-三氟乙酯-b-聚甲基丙烯酸-β-羟乙酯嵌段共聚物,用FTTR、~1H-NMR、GPC等对产物的结构与性能进行了表征。     

聚苯硫醚—聚砜嵌段共聚物的合成及初步表征

用巯端基聚苯硫醚（ＰＰＳ）齐聚物和氯端基聚砜（ＰＳＦ）齐聚物，在极性溶剂中常压合成了ＰＰＳ－ＰＳＦ嵌段共聚物，用红外光谱表征了其链结构，Ｘ－射线衍射及热分析测试结果表明，由于无定形砜基的引入，导致了嵌段共聚物的结晶度和熔融温度的下降。在合成ＰＰＳ－ＰＳＦ嵌共聚物的基础，合成了ＰＳＦ－ＰＰＳ－ＰＳＦ三嵌段共聚物，用红外光谱及Ｘ－射线衍射等分析手段对其进行了初步表征。     

嵌段共聚物PAN-b-PZDMA的合成及表征

使用原子转移自由基聚合法(ATRP)设计合成了大分子引发剂PAN-Br,通过引发甲基丙烯酸锌单体聚合制备得到黏均相对分子质量(简称黏均分子量,下同)分别为7 507、8 517、9 905的嵌段共聚物聚丙烯腈-b-聚甲基丙烯酸锌(PAN-b-PZDMA),利用1HNMR和FTIR确认了大分子引发剂和嵌段共聚物的分子结构。TGA和DSC测试结果显示,ZDMA链段抑制了聚丙烯腈的环化反应,提高了聚合物的热性能。     

PA6-b-PPG嵌段共聚物的合成与表征

以己内酰胺、己二酸、聚丙二醇(PPG)等为原料,采用高压反应釜进行熔融缩聚,合成了一系列热塑性弹性体尼龙6-b-PPG(PA6-b-PPG)嵌段共聚物。通过傅立叶变换红外分析、核磁共振氢谱对其化学结构进行表征,通过差示扫描量热、热失重分析其热性能,通过差示扫描量热分析、广角X射线衍射及偏光显微镜分析其结晶性能,并测试了材料的力学性能。结果表明,聚合产物为PA6硬段与PPG软段的嵌段共聚物;制备的系列PA6-b-PPG嵌段共聚物熔点在209~225℃之间,起始热分解温度在380~397℃之间。随着PPG含量的增加,PA6-b-PPG嵌段共聚物从γ型结晶向α型结晶转变,密度、硬度、拉伸强度、弯曲强度逐渐降低,而断裂伸长率逐渐增加。可以通过调整软硬段的比例得到不同力学性能的PA6-b-PPG嵌段共聚物,以满足不同条件下的需求。     

Synthesis and Thermal Characterization of Some Novel ABA Block Copolymers

The synthesis of some novel ABA block copolymers is reported. The block A is a PPO while the block B is a random copoly(aryl ether sulfone), synthesized with three different molecular weights. The block copolymers were obtained by a two step procedure consisting on the functionalization of the random copoly(aryl ether sulfone) followed by a condensation with PPO. Spectroscopic techniques (¹H NMR and ¹³C NMR) were used to characterize the polymers obtained from each step. The NMR data proved the complete conversion of amino groups after the first reaction step and gave some useful insights on the completion of the second step. Copolymer formation is supported by a comparison of the thermal behavior of the block copolymers with respect to the physical blends of the two homopolymers. DSC and DMA analyses showed double glass transitions for the physical blends which could be related to the immiscibility of the two homopolymers, while, in contrast, the block copolymer showed single glass transition. Blends of ABA triblock copolymer/PPO and of ABA triblock/copoly(arylen ether sulfone)s were also prepared. These blends, tested by DSC, showed a good level of compatibility of the ABA copolymer with its singular constituents.

     

Synthesis and Characterization of Dumbbell Type Amphiphilic Block Copolymers via ATRP

Summary Dumbbell type amphiphilic block copolymers, two polymeric globules connected with poly(ethylene glycol) 2000 or 4000 (PEG 2k, PEG 4k), were synthesized and characterized. The outer polystyrene globules are hyperbranched poly(chloromethyl styrene) synthesized via atom transfer radical polymerization. The degree of branch of the hyperbranched polymer tells that the structure is rather closer to a dendrimer than a general hyperbranched polymer. The synthesized polymers have well controlled structures. The molecular weights and its distributions were chatacterized by GPC and 1H-NMR. The synthesized polymers were micellized in water using dialysis method and critical micelle concentration was measured using pyrene fluorescence method.     

Synthesis and Characterization of GAP-PEG Copolymers

ABSTRACT

A series of glycidylazide–poly(ethylene glycol) (GAP-PEG) copolymers were synthesized by cationic ring-opening polymerization of epichlorohydrin (ECH) in the presence of poly(ethylene glycol) (PEG) using borontrifluoride etherate (BF₃-etherate) as catalyst, followed by the conversion of the CH₂Cl groups of poly(epichlorohydrin) (PECH) to CH₂N₃ groups. The formation of PECH-b-PEG-b-PECH triblock copolymers was confirmed by IR, ¹H NMR, and ¹³C NMR spectroscopy. The corresponding GAP-b-PEG-b-GAP triblock copolymers were characterized by UV, IR, ¹H NMR, and ¹³C NMR spectroscopy. The copolymers have shown an increment in their molecular weights as the higher analogue molecular weight PEGs were used in the polymerizations. The thermogravimetry-differential thermogravimetry (TG-DTG) and differential scanning calorimetry (DSC) studies of the GAP triblock copolymers indicate an increase in the decomposition temperature of the azide groups of GAP block in the copolymers caused by the introduction of higher molecular weight PEG blocks. GAP-PEG copolymers have shown lower glass transition temperatures than the homo glycidylazide polymer. The nitrogen content of the GAP-PEG copolymers was estimated by various methods and the value was in good agreement with the estimated values.     

两亲性嵌段共聚物的合成及其自组装行为

采用原子转移自由基聚合（ATRP）方法合成了两亲性嵌段共聚物PSt-b-PAA。用1H NMR和GPC等手段对活性聚合进行了确认,对嵌段共聚物的结构进行了表征。两亲性嵌段共聚物在离子液体1-丁基-3-甲基咪唑六氟磷酸盐（[BM IM][PF6]）中形成胶束溶液。用透射电子显微镜（TEM）观察聚合物在离子液体中形成胶束的纳米结构。当疏水链长固定时,胶束的自组装形状主要依赖于亲水链的长度。两亲性共聚物在离子液体中可自组装成可控制结构的纳米胶束,这种纳米胶束可应用在很多领域。     

新型聚硅氧烷嵌段共聚物制备的研究进展

综述了近年来国内外嵌段聚硅氧烷的研究进展,对几种主要类型的嵌段聚硅氧烷,即纯聚硅氧主链嵌段型、聚氨酯型、聚烯烃型以及聚醚型作了较全面的总结,并对其应用前景进行了展望。     

High Pressure Synthesis and Characterization of Acrylonitrile Based Copolymers in Aqueous Free Radical Polymerization Using NMR Spectroscopy

Abstract

The influence of reaction pressure on rate of polymerization and intrinsic viscosity in acrylonitrile (AN), methyl acrylate (MA) and itaconic acid (IA) ternary suspension polymerization system has been studied using free radical forming potassium persulphate and sodium metabisulphite water soluble redox initiator pair. The resulting polymers synthesized at various reaction pressures were characterized for tacticity and composition by NMR and other spectroscopic (FT-IR. ESCA) techniques. These polymers were also subjected to differential scanning calorimetric (DSC) analysis and significant change in heat of cyclization were observed with the change in reaction pressure.     

线形-枝状碳硅两亲嵌段聚合物的合成与表面性能

通过对聚乙二醇端羟基烯丙基化及硅氢化加成反应,将疏水性有机硅基团接枝到亲水的聚乙二醇链段两端,得到有机硅接枝单元数量不同的两种线形-枝状两亲聚合物,用NMR、FTIR对其结构进行了表征,并评价了其表面活性。两种聚合物具有良好的表面活性,其临界聚集浓度(CAC)值分别为5.13×10-4mol/L和4.83×10-5mol/L,γCAC值分别为32.48 m N/m和32.21 m N/m。此外,该聚合物水溶液的表面张力-浓度曲线呈现"两段式"变化,说明聚合物分子在空气/水表面上有构象变换过程,而聚合物PEG链段、含硅枝状结构将显著影响吸附层中聚合物的分子构象。     

Synthesis and Characterization of Polystyrene-b-Poly(4-vinyl pyridine) Block Copolymers by Atom Transfer Radical Polymerization

We aimed at the synthesis of well-define PS-b-P4VP by using atom transfer radical polymerization in two-step process. First, polystyrenes with benzyl bromide end group (PS-Br; by ATRP) were prepared as macroinitiator for the next ATRP of 4-vinyl pyridine and characterized these polymers from ¹H-NMR and MALDI-TOF. Comparing with MALDI-TOF-MS, ¹H-NMR and GPC analyses, this indicates that the formation of the block copolymer can be observed. During the polymerizations, molecular weight distribution and kinetics have been evaluated from GPC traces and ¹H-NMR analyses. We further characterized the thermal properties of these block polymers by DSC and TGA. DSC measurement on the PS-b-P4VP block copolymers exhibited two glass transitions, indicating that the resulting block copolymers are phase separated. Two maxima differential peaks were observed on the TGA trace for the PS-b-P4VP block copolymers might be assigned to the decomposition of the P4VP blocks at 380 ^○C and the PS blocks at higher temperature.