DMDAAC-AM反相微乳液体系的制备及聚合

以非离子表面活性剂Span-80和OP-10为复配乳化体系,煤油为油相,二甲基二烯丙基氯化铵(DMDAAC)和丙烯酰胺(AM)为单体,采用电导法和目测法相结合的方式,考察了乳化剂的亲水疏水平衡(HLB)值、水相单体浓度和配比、电解质、温度和乳化剂浓度等因素对体系稳定性和水相增溶量的影响. 结果表明,HLB为7.70、水溶液中单体浓度为60%、DMDAAC/AM摩尔比为0.2、水相中甲酸钠浓度为1.25%时,体系的电导率变化较为平稳,增溶水量也较多,温度的升高对体系的稳定性有反作用. 对该体系进行聚合,可得到澄清稳定的聚合物微胶乳. 比较聚合前后体系的粒径分布发现,聚合物粒子的体积明显增大,表明聚合过程符合单体扩散和胶束碰撞两种机理.     

阳离子聚丙烯酰胺絮凝剂的研制

以丙烯酰胺(AM)和甲基丙烯酰氧乙基三甲基氯化铵(DMC)为单体,在氧化还原引发体系中,通过水溶液聚合法合成了阳离子型聚丙烯酰胺聚合物(CPAM)。讨论了聚合单体质量分数、反应时间、反应体系温度、pH等因素对聚合反应的影响。结果表明,合成高分子量和阳离子度CPAM的最佳聚合条件为:聚合单体浓度为15%,引发剂0.06%,反应体系温度85℃,pH值为6左右,反应时间3 h。     

用于可再分散乳胶粉的阳离子苯丙乳液的合成

采用种子乳液聚合法,以十六烷基三甲基溴化铵(CTAB)为乳化剂,偶氮二异丁眯盐酸盐(AIBA)为引发剂,引入亲水性阳离子单体甲基丙烯酰氧乙基三甲基氯化铵(DMC)及功能性单体丙烯酰胺(AM)〔m(DMC)∶m(AM)=1∶1〕来制备用于可再分散乳胶粉的阳离子苯丙乳液。探讨了聚合反应温度、乳化剂用量、引发剂用量、种子单体用量、阳离子单体用量等对乳液及可再分散乳胶粉性能的影响。确定最佳配方和工艺条件为:聚合反应温度为(80±2)℃、DMC添加量为2%(以主要聚合单体质量计,下同)、CTAB用量为2%(以单体总质量计,下同)、AIBA用量为0.53%(以单体总质量计,下同)、种子单体用量为10.0%(以单体总质量计,下同)。在该工艺条件下,合成的阳离子苯丙乳液粒径大小和分布适中、性能稳定,由其所制得的可再分散乳胶粉含水率低、平均粒径小、再分散性优良。     

CPAM的合成及影响因素分析

以甲基丙烯酰氧乙基三甲基氯化铵(DMC)和丙烯酰胺(AM)为聚合单体,以亚硫酸氢钠和过硫酸铵为引发剂,通过水溶液聚合法聚合得到阳离子聚丙烯酰胺(CPAM)。考察了聚合单体的质量分数、引发剂的用量、反应时间、反应温度及p H等因素对聚合物相对分子质量的影响。实验结果表明,合成高相对分子质量的CPAM的较优聚合条件是:聚合单体的质量分数为15%,引发剂0.3%,反应温度80℃,p H值为7,反应时间为3 h,相对分子质量可达5.91×106。     

丙烯酸酯弹性乳液的制备及性能研究

以N-羟甲基丙烯酰胺和甲基丙烯酸作为功能单体,使用阴、非离子型和反应性的复配乳化剂体系,采用种子预乳化和半连续聚合工艺,制备具有核壳结构的丙烯酸酯弹性乳液。研究了单体配方、聚合温度、乳化剂、功能单体、引发剂等对乳液性能的影响。研究结果表明：当核层玻璃化温度为-19.7℃、壳层温度为4.3℃、核壳单体总量比为3∶2,成膜稳定,连续性好;采用丙烯酰胺基异丙基磺酸钠（AMPS）、十二烷基苯酸钠（SDBS）、聚乙二醇辛基苯基醚（OP-10）乳化剂体系且比例为1∶1∶1,用量为单体总量的3%,引发剂用量为0.5%,NMA和MMA的用量分别为1%和2%,核壳聚合温度分别为52℃和80℃,能制备出耐沾污性、耐水性、延伸率等各性能良好的具有核壳结构的丙烯酸酯弹性乳液。     

快干型水性干法复膜胶的合成

以丙烯酸丁酯(BA)为软单体、苯乙烯(St)为硬单体、N-羟甲基丙烯酰胺(NMAM)为交联剂,采用阴/非离子型复合乳化剂(CO-459)和水性催干剂(H-874),制成一种快干型水性干法复膜胶。研究结果表明:当w(CO-459)=1.5%和w(NMAM)=1.0%～2.5%(相对于单体总质量而言)、m(底加乳化剂)∶m(总乳化剂)=30∶100、m(BA)∶m(St)=1∶(0.45～0.65)、反应温度为85～90℃、单体滴加时间为2.0 h、保温时间为1.5 h和w(H-874)=1.2%时,相应复膜胶乳液的聚合稳定性较高、存储期较长且综合性能满足使用要求,并且其干燥速率相对较快。     

反相乳液聚合制备阳离子型高分子絮凝剂P(DMC-AM)

以丙烯酰胺(AM)和甲基丙烯酰氧乙基三甲基氯化铵(DMC)为共聚单体,石蜡为连续相,Span80和OP10为复合型乳化剂,通过反相乳液聚合制备高分子阳离子共聚物P(DMC-AM),研究了引发剂用量、乳化剂用量、单体质量分数、油水质量比以及聚合体系pH值等聚合条件对聚合物相对分子质量的影响.最佳工艺条件为:引发剂V-50用量为1.4‰、乳化剂用量为6%,EDTA-2Na用量为1.0‰、亲水亲油平衡值为6、单体质量分数为40%、单体配比为n(DMC):n(AM)=5:95,油水质量比为1.1:1.0,pH值为5、反应温度为50℃及反应时间为4 h.在上述条件下,所得产物的相对分子质量可达589×10~4.并通过FT-IR和DSC-TGA对产物结构和热稳定性进行表征.     

丙烯酸酯乳液的合成及改性研究

以丙烯酸丁酯(BA)和丙烯酸-2-乙基己酯(2-EHA)为软单体、甲基丙烯酸甲酯(MMA)为硬单体、丙烯酸(AA)为功能单体、甲基丙烯酸羟乙酯(HEMA)为交联单体和十二烷基硫酸钠(SDS)/乳化剂(OP-10)为阴/非离子型复合乳化剂,采用核/壳种子乳液聚合法制备了丙烯酸酯共聚乳液;然后在壳层聚合时寸加入HEMA,并用乙烯基有机硅进行改性,制得硅丙乳液。结果表明:当m(SDS):m(OP-10)=3:2、w(复合乳化剂)=3.4%、w(引发剂)=0.82%、w(HEMA)=3.5%、聚合温度为80℃以及聚合中期加入6.8%乙烯基硅油至壳单体中时,硅丙乳液及其胶膜的稳定性、耐水性和力学性能俱佳。     

用阳离子可聚合表面活性剂超声辐照乳液聚合制备聚合物纳米粒子

合成了一种阳离子可聚合表面活性剂甲基丙烯酰氧乙基十二烷基二甲基溴化铵(C12N+),应用于超声辐照苯乙烯乳液聚合中,采用红外光谱、表面张力测试、核磁共振氢谱、透射电镜对聚合产物的结构和形貌进行了表征。结果表明,可聚合表面活性剂与苯乙烯发生了共聚反应,且反应完全,制备了高纯聚合物纳米胶乳。实验证明,C12N+同时起到了乳化剂、引发剂和共聚单体三重作用,与用一般乳化剂十二烷基硫酸钠(SDS)相比,表现出引发效率高(诱导期<15 m in)、反应速率快(最大反应速率为SDS体系的3倍)、低声强下单体转化率高(反应60 m in单体转化达到90%以上)、无乳化剂残留的优点。     

硅烷偶联剂改性丙烯酸酯乳液的合成及性能研究

以甲基丙烯酸甲酯(MMA)和丙烯酸丁酯(BA)为主单体,硅烷偶联剂为交联单体,合成自交联丙烯酸酯乳液,探究复合乳化剂、乳化剂用量和硅烷偶联剂添加量等因素对乳液性能的影响。结果表明,采用半连续种子乳液法作为聚合方法,当乳化剂配比DNS-86∶LCN-287=2∶1,乳化剂用量为3%,3-(异丁烯酰氧)丙基三甲氧基硅烷(A-174)质量分数占总单体的4%,制备的丙烯酸乳液具有优良的稳定性,单体转化率为92.93%,凝胶率<1%。硅烷偶联剂的使用能够提高聚合物的交联度、耐热性和耐水性。     

无机-两性聚丙烯酰胺混凝脱除有机废水中的磷

利用丙烯酰胺(AM)、丙烯酸(AA)、丙烯酰氧乙基三甲基氯化铵(DAC)、2-丙烯酰胺-2-甲基丙磺酸(AMPS)制备含有阴离子和阳离子基团的两性聚丙烯酰胺(ACPAM)反相乳液,考察了反相乳液分别与聚氯化铝(PAC)、聚氯化铁(PFC)和聚氯化铝铁(PFAC)三种无机絮凝剂对高含磷有机废水混凝脱磷的效率,PFC的脱磷...     

阳离子型含氟丙烯酸酯共聚乳液的微波辐射制备

在微波辐射下,以十八烷基三甲基氯化铵为乳化剂,2,2-偶氮2甲基丙基脒-二盐酸盐（AIBA）为引发剂,将丙烯酸丁酯（BA）、甲基丙烯酸甲酯（MMA）、甲基丙烯酸十二氟庚酯（GO-4）以及甲基丙烯酰氧乙基三甲基氯化铵（DMC）进行乳液聚合,成功制备了Zeta电位在315mV左右、粒径为55~75nm的阳离子型含氟丙烯酸酯乳液。通过测定乳胶膜中氟元素含量,发现微波辐射能提高含氟单体共聚效率,使乳胶膜中氟元素含量增加。用固含量1％的阳离子型含氟丙烯酸酯共聚物乳液处理棉布织物,结果发现,棉布对水和正十六烷的接触角可分别达到111．3°、60．6°,表面自由能降至1581mJ／m2,棉布的静态吸水时间可以超过4h。     

Influences of the polymerization ingredients on the porous morphology of soap‐free poly(methyl methacrylate/ethyl acrylate/methacrylic acid) seeded latex particles

Monodispersed soap‐free poly(methyl methacrylate/ethyl acrylate/methacrylic acid) latex particles were synthesized by the seeded emulsion polymerization of methyl methacrylate, ethyl acrylate, and methacrylic acid (MAA), and particles with a porous morphology were obtained after an alkali posttreatment. The effects of the unsaturated acid and crosslinking agent on the properties and morphology of the latex particles were investigated. The results showed that the particle size decreased and its distribution widened when the concentration of MAA was greater than 10.0 mol % or the concentration of ethylene glycol dimethacrylate (EGDMA) was greater than 1.5%. When more than 4.0 mol % MAA was used, a porous structure could be detected clearly under a transmission electron microscope, and the particle volume and pore size first gradually increased to a maximum and then decreased rapidly with an increase in the MAA concentration. The porous morphology disappeared completely as the MAA concentration reached 16.0 mol %. A multihollow morphology was generated when the EGDMA concentration exceeded 1.0%, and the particle volume decreased monotonously with the concentration of EGDMA increased. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1934–1939, 2006     

聚合型紫外线吸收剂的合成研究Ⅰ.含2-羟基-4-丙烯酸酯基二苯甲酮的丙烯酸酯类乳液聚合

通过“粒子设计”利用核壳乳液聚合技术以功能型紫外线吸收剂、苯乙烯、丙烯酸丁酯、甲基丙烯酸甲酯、丙烯酸乙酯为单体制备出核壳结构的聚合物乳胶粒。其中,功能型紫外线吸收剂2-羟基-4-丙烯酸酯基二苯甲酮由2,4-二羟基二苯甲酮和丙烯酰氯制备。通过紫外分光光度法测试,此乳胶粒的吸收度大于同浓度下的功能型单体及2,4-二羟基二苯甲酮。     

甲基丙烯酸甲酯-丁二烯-苯乙烯树脂的合成及其对聚氯乙烯的改性

采用种子乳液接枝聚合技术合成了甲基丙烯酸甲酯(MMA)-丁二烯-苯乙烯树脂(MBS),考察了复合乳化剂浓度、CO2用量对丁苯胶乳粒径及其分布、胶乳稳定性的影响;研究了接枝单体滴加方式和接枝聚合反应温度对MBS体系稳定性和接枝效率的影响;讨论了MBS改性聚氯乙烯(PVC)的影响因素;提出了丁苯胶乳的碳酸化扩径附聚法和MBS胶乳的SO2凝聚新工艺。结果表明:在丁二烯/苯乙烯(质量比)为90/10、阴离子/非离子复合乳化剂浓度为35~40g/L、丁苯胶乳采用CO2附聚扩径、部分MMA预溶胀和其余MMA连续滴加的方式以及MBS胶乳SO2凝聚新工艺的条件下,所得MBS树脂粉料颗粒均匀,40~180目的颗粒质量分数达96%,堆积密度在0.4g/cm3以上;PVC/MBS(质量比为100/8)共混物的冲击强度达22.6kJ/m2。     

Preparation of cationic functional polymer latexes and measurement of involatile monomer conversion

A series of poly(styrene‐co‐methacryloxyethylhexadecyldimethyl ammonium bromide), P(St‐DMHB), cationic particles were prepared by emulsion polymerization using 2,2′‐azobis(2‐methylpropionamide) dihydrochloride as the initiator with different levels of DMHB as the cationic functional comonomer. ζ potential, particle size, and size distribution of the particles were determined. Large discrepancy was observed between the particle size from dynamic light scattering and that from transmission electron microscopy. Results showed that particle size and ζ potentials were closely dependant on DMHB level used. A flocculation process for the cationic latex was established, and a method to estimate DMHB conversion was proposed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Emulsifier‐free emulsion copolymerization of styrene with quaternary ammonium cationic monomers

Emulsifier‐free emulsion binary copolymerizations of styrene with four types of quaternary ammonium cationic monomers, diallyldimethylammonium chloride (DADMAC), (3‐(methacryloylamino) propyl) trimethyl ammonium chloride (MAPTAC), (2‐methacryloyloxy) ethyl) trimethyl ammonium chloride (MATMAC), and vinylbenzyl trimethyl ammonium chloride (VBTMAC), were conducted at 70°C. 2, 2'‐azobis (2‐methylpropionamidine) dihydrochloride (V50) and potassium persulphate (KPS) were used as cationic and anionic initiator, respectively. Ternary copolymerizations were also carried out in the presence of acrylamide as a second comonomer. Monomer conversions were followed by ultraviolet spectroscopy and the polymer microparticles were characterized using photon correlation spectroscopy, electrophoresis, colloid titration, and scanning electron microscopy. The results indicated that VBTMAC and MATMAC were highly reactive in the copolymerization with styrene whereas the incorporation of DADMAC was slow. MAPTAC had an intermediate reactivity. Binary copolymerization with VBTMAC, MATMAC, and MAPTAC produced particles smaller in size, but higher in surface‐charge density, than styrene homopolymer particles. However, significant agglomerates were detected in the VBTMAC and MATMAC‐containing latexes. In contrast, DADMAC‐containing polymer particles were almost identical to styrene particles. Continuous nucleation took place in the binary copolymerizations with VBTMAC and with MATMAC when using V50 initiator. In the case of using KPS, VBTMAC‐containing particles grew continuously to a mean size much larger than the corresponding particles initiated by V50. The presence of acrylamide reduced DADMAC‐containing particle size and diminished the agglomeration in the VBTMAC‐ and MATMAC‐containing latexes. The results were interpreted via particle formation mechanism. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1129–1140, 2000     

阳离子型全氟丙烯酸酯无皂乳液的合成及性能

以全氟烷基乙基丙烯酸酯(FEA)为含氟单体,以甲基丙烯酰氧乙基三甲基氯化铵(DMC)为阳离子单体,采用无皂乳液聚合方法合成了阳离子型全氟丙烯酸酯共聚物乳液.分析了FEA含量对涂膜性能的影响,讨论了DMC用量对聚合转化率、涂膜吸水率以及乳胶粒粒径大小的影响;利用FT-IR和X-射线衍射分析(XRD)对共聚物乳液进行了表征,结果表明,当FEA和DMC质量分数分别为7.1%和12%时,涂膜的吸水率最小,仅为3.75%,乳胶粒平均粒径为65 nm.随着FEA量的增加,共聚物膜的硬度减小,拉伸强度增加,断裂伸长率降低;XRD分析显示全氟丙烯酸酯无皂乳液具有好的结晶性.     

大粒径聚丙烯酸丁酯胶乳的制备

采用种子乳液聚合法制备了丙烯酸酯-苯乙烯-丙烯腈共聚物生产工艺中的基础胶乳聚丙烯酸丁酯(PBA),考察了配方和工艺条件对其粒径增大的影响。结果表明,在合成种子胶乳时可加入质量分数0.2%～0.8%的乳化剂十二烷基硫酸钠;在种子胶乳粒径放大试验时,加入质量分数0.3%的乳化剂十二烷基硫酸钠及补加的单体量为种子胶乳总固体物质量的33倍可以得到大粒径的PBA胶乳。采用种子乳液聚合法进行PBA胶乳粒径放大方法简便、效果明显。