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。     

一端接异氰酸酯基的聚丙烯酸酯低聚物的合成及表征

用两步法合成出一端接异氰酸酯基(—NCO)的聚丙烯酸酯低聚物。首先以甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)为单体,巯基乙醇(2-ME)为链转移剂,低浓度的偶氮二异丁腈(AIBN)为引发剂,在110℃将按n(MMA):n(BA):n(2-ME):n(AIBN)=500:500:25:1配制的溶液,在2.5h内滴加到甲苯中,反应4h,得到多分散系数Mw/Mn=1.8、一端带羟基的聚丙烯酸酯低聚物〔(MMA—BAOH〕;再加入甲苯-2,4-二异氰酸酯(TDI)与其端羟基反应,合成出一端接异氰酸酯基的聚丙烯酸酯低聚物〔(MMA—BANCO〕。该低聚物结构与热性能用FTIR、1HNMR、13CNMR、GPC、DSC、TGA进行了表征。结果表明,产物的分子结构符合分子设计,即一端接有异氰酸酯基(—NCO),数均相对分子质量Mn在4500左右,DSC显示合成的低聚物的Tg在40℃左右,TGA测出其主要热失重在300～450℃。该低聚物可作为大分子表面改性剂,用于氮化硅、氮化铝等纳米粉体的表面修饰改性。     

原子转移自由基聚合合成三烷氧基硅单封端的聚甲基丙烯酸甲酯

合成和表征了氯乙酰氨丙基三乙氧基硅烷。以其为引发剂，在氮化亚铜／联吡啶存在下，引发甲基丙烯酸甲酯进行原子转移自由基聚合，合成了大分子链端含三乙氧基硅基团的聚甲基丙烯酸甲酯。用1H—NMR，FTIR，GPC和元素分析等对聚合物进行表征。GPC分析结果显示，产物的平均相对分子质量与理论计算值很接近，具有较小的相对分子质量多分散系数。DSC和TG结果显示，产物的Tg为78℃，最快热失重出现在347.2℃左右。     

分批投料法制备组成均匀的甲基丙烯酸甲酯/马来酸酐共聚物

分别采用一次投料法和计算机模拟分批投料法制备甲基丙烯酸甲酯/马来酸酐共聚物[P(MMA-co-MAh)],通过红外光谱(IR)、核磁共振(NMR)、凝胶色谱(GPC)、热失重分析(TGA)、示差扫描量热法(DSC)进行表征,比较了这两种方法制备的共聚物在结构和性能上的差异。GPC测试表明,一次投料法和分批投料法对产物的相对分子质量影响不大;IR和NMR测试表明,分批投料法制备的产物的组成是均匀的;DSC测试表明,一次投料法反应前后期制备产物玻璃化温度存在差异,分批投料法反应前后期制备的产物玻璃化温度基本相同;TGA测试表明,在400~550℃时,分批投料法制备的产物的热稳定性较好。     

PGMA-b-PS二嵌段共聚物的RAFT/细乳液合成及表征

以2-(十二烷基三硫代碳酸酯)-2-甲基丙烯酸为链转移剂,利用RAFT/细乳液联合技术合成了相对分子质量分布较窄(PDI=1.53)的大分子链转移剂聚甲基丙烯酸缩水甘油酯。再以该大分子为可逆加成-断裂链转移(RAFT)试剂,通过连续加料的方式加入苯乙烯后进一步引发聚合,得到PGMA-b-PS二嵌段共聚物。采用GPC、FT-IR、1H-NMR、DSC等方法对聚合产物进行了表征。结果表明:合成的聚合物为线型二嵌段共聚物,相对分子质量分布为1.87,该聚合过程具有活性/可控特征。DSC测得二嵌段共聚物具有2个玻璃化转变温度(Tg),分别为77.33℃和98.30℃。此外,还考察了单体加料顺序对聚合过程的影响。     

聚苯丙微乳液的结构表征

采用种子微乳液聚合工艺合成了聚苯丙微乳液，用FFIR、DSC、GPC等分析手段研究了微乳聚合物的分子结构。FTIR和DSC测试结果显示出4种单体都参与了共聚反应，无均聚物存在，合成的苯丙微乳液共聚物的疋约为34．6℃，明显高于理论值（25℃）。GPC分析结果说明苯丙微乳聚合物具有很高的相对分子质量。马尔文纳米粒度及Zeta电位分析仪测定苯丙微乳聚合物平均粒径为38nm，且成正态分布。     

ε–己内酯/聚醚/环氧丙烷三元共聚物的合成及表征

采用双金属氰化络合物(DMC)催化剂进行低相对分子质量聚醚二元醇(DLL400)、ε–己内酯(CL)和环氧丙烷(PO)阴离子开环共聚反应,合成了聚醚酯多元醇。凝胶渗透色谱(GPC)分析和CL单体转化率、羟值、黏度等测试结果表明:合成的最佳反应温度为160℃,反应时间为5 h,催化剂用量为150 mg/kg。通过FT–IR(傅里叶转换红外光谱)、1H–NMR(核磁共振)、13C–NMR对该共聚物进行表征,表明所合成共聚物具有预期结构。     

苯乙烯-N-苯基马来酰亚胺-马来酸酐三元共聚物的合成、性质及应用

采用溶液及微乳液两种聚合法,合成苯乙烯-N-苯基马来酰亚胺-马来酸酐(St-NPMI-MAH)三元共聚物。通过IR,1HNMR,13CNMR,GPC表征共聚物结构,溶液聚合产物为嵌段共聚物,乳液聚合产物为无规共聚物。采用DSC、TGA研究共聚物的热性能,溶液聚合产物的玻璃转化温度为212.9℃,5%热失重温度为348℃;微乳液聚合产物的玻璃转化温度为214.4℃,5%热失重温度为374℃。     

直接熔融聚合法合成生物降解材料PLEG研究 V反应机理

直接以乳酸(LA)单体和聚乙二醇(PEG)为原料,通过直接熔融共聚法,合成了生物降解材料聚乳酸-聚乙二醇(PLEG),用特性粘数[η]、GPC、FTIR1、H NMR、DSC和X-射线衍射等手段对其进行了系统的表征,发现许多因素对PLEG存在一定的影响,如不同的预聚方式时PLEG的组成不同、左旋乳酸(L-LA)获得的共聚物相对分子质量不如外消旋乳酸(D,L-LA)等。在此基础上,初步探讨了LA与PEG直接熔融共聚的反应机理。     

DMS溶液法合成苯乙烯-马来酸酐无规共聚物

以环保型溶剂丁二酸二甲酯(DMS)为溶剂、苯乙烯(St)和马来酸酐(MAn)为共聚单体,采用溶液聚合法合成了苯乙烯/马来酸酐无规共聚物(R-SMA)。分析了溶剂浓度、单体摩尔比等反应条件对共聚物的影响,并且将其与传统常用溶剂丁酮进行对比。利用红外光谱(FTIR)表征R-SMA化学结构,采用凝胶气相色谱(GPC)测定其分子量及分子量分布,采用差示扫描量热法(DSC)、热重分析法(TGA)分析了R-SMA的热性能。实验结果表明,在溶剂DMS质量分数为70%、St/MAn摩尔比为75/25、反应温度为120℃条件下,R-SMA收率为82.9%、数均分子量(M_n)为18 111,分子量分布指数(PDI)为2.0。与丁酮作溶剂相比,当DMS作为溶剂时,产物的相对分子质量及马来酸酐含量较好,耐热性相近。     

Synthesis of tercopolymer BA–MMA–VTES and surface modification of nano‐size Si3N4 with this macromolecular coupling agent

A new macromolecular coupling agent butyl acrylate (BA)‐methyl methacrylate (MMA)‐vinyl triethoxy silane (VTES) tercopolymer was synthesized using solution polymerization initiated by free radical initiator benzoyl peroxide (BPO) and dicumyl peroxide (DCP). Dodecylthiol is choosed as the chain transfer to control the molecule weight of this tercopolymer. The terpolymer's molecular structure was confirmed by FTIR and NMR, and its average molecular weight was determined by GPC. In this work, the tercopolymer BA–MMA–VTES is used for surface modification of silicon nitride (Si₃N₄) nanopowder. The structure surface properties and thermal stability of modified nano‐Si₃N₄ were systematically investigated by FTIR, TGA, TEM, and size distribution analyzer. The results show that the macromolecular coupling agent bonds covalently on the surface of nano‐sized Si₃N₄ particles and an organic coating layer is formed. The optimum loading of this macromolecular coupling agent BA–MMA–VTES tercopolymer is 5% (wt %) of nano‐sized Si₃N₄. TEM also reveals that modified nano‐Si₃N₄ possesses good dispersibility. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Surface modification of MWNTs with BA‐MMA‐GMA terpolymer by single‐step grafting technique

In this article, a facile strategy was developed to prepare BA‐MMA‐GMA/MWNTs (multiwalled carbon nanotubes) hybrid nanoparticles as nanofillers in rubber by single‐step grafting technique. First, a new macromolecular surface modifier butyl acrylate (BA)‐α‐methyl methacrylate(MMA)‐glycidyl methacrylate (GMA) terpolymer was synthesized via radical copolymerization. Afterward, this terpolymer modifier was covalently grafted onto the surface of crude MWNTs by single‐step grafting technique. The structure, surface properties, and thermal stability of modified MWNTs were systematically investigated by FTIR, TGA, and TEM. FTIR results showed that BA‐MMA‐GMA terpolymer was successfully grafted onto the surface of MWNTs. TGA indicated that the optimum mass fraction of macromolecular modifier coated on the surface of MWNTs was 9 wt %. TEM images revealed that an organic coating layer was formed and the modified MWNTs showed good dispersibility in acetone. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

端羧基聚乳酸的扩链、改性及其性能

以丙交酯为原料、辛酸亚锡为催化剂、丁二酸酐为改性剂,采用梯度升温法,在150℃、0.098MPa条件下采用直接熔融缩聚法合成端羧基聚乳酸共聚物P(LA/SA),接着用2,2-(1,3-亚苯基)-二 唑啉(1,3-PBO)对其进行扩链,按n(丙交酯)/n(1,3-PBO)= 1/2.4加入1,3-PBO,反应1h制得聚酰胺酯(PEA),最后将高岭土与PEA在150℃、减压条件下熔融复合改性。采用GPC、FTIR、¹H NMR、DSC、SEM等手段对聚合物的结构进行表征和性能测试,结果表明,与P(LA/SA) 相比,扩链产物PEA相对分子质量大幅度提高,重均相对分子质量高达24万,玻璃化转变温度T_g高于PLA和P(LA/SA),改性后复合材料的热稳定性能提高,结晶度降低。     

四苯乙炔基硅烷的合成及热性能研究

为得到耐热的含有苯乙炔官能团的有机硅单体,通过苯乙炔锂(由苯乙炔与丁基锂制得)与四氯硅烷的反应,合成了四苯乙炔基硅烷(TPES),通过多次重结晶获得了纯度为99.5%的TPES,并用FTIR、1HNMR、13C NMR、29Si NMR及元素分析对其结构进行了表征。对TPES及其400℃固化物的DSC、FTIR和TGA的分析表明:TPES的熔融温度范围宽达113℃(199℃~312℃);在氮气中失重5%时的温度Td5为710.8℃,800℃残炭率高达93.3%,空气中的Td5为595℃,800℃残炭率也达58.3%,耐热性能十分优异,具备作为一种耐高温聚合物材料的优秀潜质。     

Synthesis and characterization of cationic gemini surfactant modified Na–bentonite and its applications for rubber nanocomposites

A cationic gemini surfactant (N‐isopropyl‐N , N‐dimethyldodecan 1‐aminium bromide) was synthesized by quaternization reaction. The synthesized surfactant was characterized by Fourier transform infrared (FTIR) and proton nuclear magnetic resonance (1H NMR) spectroscopy. Modified Na–bentonite (organoclay) was obtained by the intercalation of a gemini surfactant between the layers of sodium bentonite and characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), FTIR, thermogravimetry–differential thermal analysis (TGA–DTA) and differential scanning calorimetry (DSC) techniques. The results of XRD, TEM, FTIR, TGA, and corresponding DSC analysis indicate that gemini surfactant has been successfully intercalated into the clay layers. Rubber‐based nanocomposites have been prepared by incorporating various concentration of organically modified bentonite on to natural rubber/styrene–butadiene rubber (NR/SBR) rubber blend (75/25) using two roll mill. Effect of organoclay content on XRD, curing, mechanical, and scanning electron microscopy (SEM) properties of the nanocomposites are investigated. The morphological study showed the intercalation of nanoclay in NR/SBR blend chain. It was found that the organoclay decrease the optimum and scorch time of the curing reaction, increase maximum torque and the curing rate, which was attributed to the further intercalation during vulcanization process. Mechanical properties such as tensile strength, modulus and elongation at break have improved. POLYM. COMPOS., 38:396–403, 2017. © 2015 Society of Plastics Engineers     

星形聚丁二酸丁二醇酯的合成及性质

以丁二酸、丁二醇、丙三醇为原料,通过熔融缩聚合成了三臂星形结构的聚丁二酸丁二醇酯（s-PBS）,运用红外光谱、凝胶渗透色谱、差示扫描量热仪、热重分析仪和偏光显微镜对其进行了表征及性能研究。结果表明,合成的s-PBS的数均相对分子质量为7.32×104,结晶度约为76 %,熔点为115.4 ℃ ,在堆肥培养液中降解60 d后的生物降解率达54.16 %。     

Synthesis and characterization of macromolecular surface modifier PP--PEG for polypropylene

A novel macromolecular surface modifier, polypropylene-grafted-poly(ethylene glycol) copolymer (PP-g-PEG), was synthesized by coupling polypropylene containing maleic anhydride with monohydroxyl-terminated poly(ethylene glycol). The effects of the reaction condition on the graft reactions were studied. The copolymers were characterized by IR, ¹H NMR, thermogravimetry (TG) and differential scanning calorimetry (DSC). The results indicated that the graft reactions were hindered by increasing the molecular weight of PP or PEG. The graft copolymer was found to have a higher initial thermal degradation temperature and lower crystallization capacity as compared with pure PP, and the side chain of PEG hindered the PP chain from forming a perfect ? crystal. The thermal stability of PP-g-PEG decreased with the increasing content or molecular weight of PEG. The copolymers were blended with polypropylene to modify the surface hydrophilicity of the products. The results of attenuated total reflectance FTIR spectroscopy (ATR-FTIR) showed that PP-g-PEG could diffuse preferably onto the surface of the blends and be suitable as an effectual macromolecular surface modifier for PP.     

螺环二醇改性PET共聚酯的合成及性能

为了扩大聚对苯二甲酸乙二醇酯（PET）的应用范围,常通过引入第三单体来改变其性能。本研究以螺环二醇（SPG）为原料,采用酯交换法熔融缩聚合成了一系列不同单体含量的共聚酯。采用超高效聚合物色谱-多角度激光光散射仪（APC-MALLS）联用分析了共聚酯的分子量与分子量分布,利用核磁氢谱（¹H NMR）、傅里叶红外光谱（FTIR）研究了共聚酯的化学结构,同时采用差示扫描量热仪（DSC）、热重分析仪（TGA）和X射线衍射仪（XRD）研究了共聚酯的热性能以及结晶性能,测试了共聚酯的拉伸性能。结果表明,成功合成了符合纤维级聚酯数均分子量（M_n）和重均分子量（M_w）要求的共聚酯,分子量分布较窄,随着第三单体含量的增加,玻璃化转变温度从77℃提升至85℃,而熔融温度从255℃降低至222℃,热分解温度无明显变化,结晶性能下降。     

苯酚-亚联苯型酚醛树脂的合成与表征

以苯酚及4,4′-二（氯甲基）联苯为单体,盐酸作催化剂经Friedel-Crafts烷基化反应,合成了苯酚-亚联苯型酚醛树脂。利用傅里叶红外光谱（FTIR）、核磁共振（1H NMR、13C NMR）、凝胶渗透色谱（GPC）与热失重分析（TGA）对产物的结构、分子量、分子量分布及耐热性进行了表征与测定。结果表明：经Friedel-Crafts烷基化反应所得到的苯酚-亚联苯型酚醛树脂系邻、对位取代的混合物。随着苯酚用量的增大,苯酚-亚联苯型酚醛树脂的相对分子量逐渐减小,分子量分布逐渐变窄。产物耐热性能优异,起始分解温度能达到340℃。