丙烯酸酯核壳乳液胶膜力学性能研究

采用种子乳液聚合法制备了丙烯酸(AA)/丙烯酰胺(AM)交联的、具有核壳结构的甲基丙烯酸甲酯(MMA)/丙烯酸丁酯(BA)/丙烯腈(AN)复合乳液,研究了壳层软硬单体比、复合交联剂AA/AM及壳层交联单体AN用量对乳液胶膜拉伸强度和断裂伸长率的影响。结果表明:当核层和壳层之间的玻璃化转变温度Tg相近时,核壳乳液核、壳两部分分子链的协调运动能力较强,其乳液胶膜拉伸强度和断裂伸长率都较大;当AA/AM用量不超过4%时,乳液胶膜强度和断裂伸长率随着AA/AM用量增大而增大;随着AN用量的增加,乳液胶膜拉伸强度逐渐增大。     

硅烷偶联剂改性苯丙乳液的合成和性能分析

以苯乙烯(St)、丙烯酸丁酯(BA)、α-甲基丙烯酸(MAA)、乙烯基三乙氧基硅烷(VTES)为原料,采用种子乳液聚合法合成了硅烷偶联剂改性苯丙乳液。研究了反应温度、水解抑制剂、软硬单体配比、VTES加入方式及用量对乳液性能的影响。得出最佳工艺:反应温度为75~80℃,熟化温度为90℃,中和温度为40℃;m(St)∶m(BA)=4∶5,乳化剂的用量为单体总质量的4.5%,水解抑制剂乙二醇的用量为单体总质量的5%,VTES的用量为单体总质量的5%。按此工艺制得的VTES改性苯丙乳液的外观、钙离子稳定性、冻融稳定性、成膜性都较好;与纯苯丙乳胶膜相比,其乳胶膜的吸水率更低,耐有机溶剂性更好,Tg升高5℃,耐热性有所提高。     

丙烯酰胺改性丙烯酸酯乳液的合成及性能研究

通过预乳化半连续法制备了丙烯酰胺(AM)改性的丙烯酸酯乳液,探讨了功能单体AM用量对丙烯酸酯乳液和乳液胶膜性能的影响。结果表明:当AM用量为单体质量的1.0%时,乳液及乳液胶膜的综合性能最好。此时,功能单体AM改性的丙烯酸酯乳液聚合稳定性和转化率有所提高;乳液胶膜的力学性能有较大幅度的提高,吸水率有一定程度的降低。     

用磺酸型亲水扩链剂制备高固含量聚氨酯乳液

以聚(四氢呋喃-co-氧化丙烯)二醇为软段、异佛尔酮二异氰酸酯为硬段,以1,2-二羟基-3-丙磺酸钠(DHPA)作为亲水扩链剂,用自乳化法合成了一系列稳定的高固含量聚氨酯乳液,分析了DHPA用量对乳液及其胶膜性能的影响。结果表明:所得聚氨酯乳液的粒径呈多元分布,乳胶粒子呈球形;乳液为假塑性流体;随着DHPA用量的增加,乳液平均粒径逐渐减小,粒径分布变窄,固含量不断增大,当DHPA质量分数为7%时,乳液的总固物质量分数可达61%。乳液具有较好的高、低温及贮存稳定性能。随着DHPA用量的增加,聚氨酯乳液胶膜的拉伸强度逐渐增大,扯断伸长率则先增大后减小;当DHPA质量分数为5%时胶膜的综合力学性能最佳;DHPA用量对胶膜的热稳定性没有明显影响。     

水性聚氨酯改性天然胶乳膜的制备及性能

采用机械法制备水性聚氨酯(WPU)/天然胶乳(NRL)的共混乳液,自然流延并在热空气中硫化制得WPU/NRL硫化胶膜,考察了不同WPU用量下共混乳液的加工性能、胶膜硫化特性和硫化胶膜的力学性能、透气性及耐溶剂性。结果表明:随着WPU用量的增加,共混乳液的黏度上升,表面张力变化较小。WPU/NRL胶膜的正硫化时间缩短,交联密度先增大后减小;硫化胶膜的断裂伸长率降低,拉伸强度和300%定伸应力先增大后减小,硬度增大,当WPU用量为7.5份时,硫化胶膜的拉伸强度达到27.84 MPa。与NRL硫化膜相比,WPU/NRL硫化胶膜的透气性有所降低,耐溶剂性能与致密性得到改善。     

乙烯基三乙氧基硅烷/D4共聚微乳液

在十二烷基苯磺酸(DBSA)存在下,将八甲基环四硅氧烷(D4)与乙烯基三乙氧基硅烷(VTES)进行乳液共聚反应,制备了乙烯基改性的有机硅微乳液.考察了DBSA用量、原料配比等条件对乳液聚合及乳胶粒形态的影响.结果表明,当DBSA用量为体系质量的3%～4%,VTES用量为体系质量的1%～2%时,得到的微乳液较稳定;随VTES用量的增加,粒径越来越大,粒径分布越来越窄;体系的酸性较强时得到的粒子均一,分散较好,反应速率也随酸性减小而降低.     

FAGO/丙烯酸酯乳胶膜的制备及性能表征

采用种子乳液聚合法制备了丙烯酸功能化氧化石墨烯(FAGO)/丙烯酸酯纳米复合乳液,探讨了FAGO用量对FAGO/丙烯酸酯乳液粒径及乳胶膜性能的影响。通过动态光散射测试复合乳液的粒径及粒径分布、SEM表征了复合乳液的形貌,并对乳胶膜热稳定性、玻璃化温度、耐溶剂性、力学性能等性能进行测试。结果表明,FAGO/丙烯酸酯无皂复合乳液的粒径大小均一,乳胶粒子附着在FAGO片层边缘,分散性良好。随着FAGO用量的增加,复合乳液乳胶粒平均粒径逐渐变大,乳胶膜的热稳定性提高和吸水性逐渐降低,同时玻璃化温度升高,力学性能增强。     

双键封端水性聚氨酯的合成及表征

以异佛尔酮二异氰酸酯(IPDI)、聚醚二醇(N-210)、二羟甲基丙酸(DMPA)、一缩二乙二醇(DEG)及丙烯酸羟乙酯(HEA)为基本原料,经相转化法合成了一系列双键封端阴离子型水性聚氨酯(TPU)自乳化乳液。探讨了封端时间及HEA用量对封端的影响,HEA用量对乳液粒径、胶膜热性能及涂层紫外吸收的影响。FTIR测试表明,在聚合温度70℃下,HEA用量为理论用量120%时,3 h封端完全;粒径测试表明,乳液粒径随着HEA用量的增加而增大;TGA测试表明,胶膜耐热性随着HEA添加量的增加而提高;紫外吸收测试表明,随HEA用量的提高,乳液在220 nm处吸收增强。     

纳米碳酸钙改性水性双组分胶粘剂的合成与性能研究

合成了一种综合性能优良的环境友好型双组分粘合剂,并对其进行性能研究:采用旋转粘度计研究了PVA含量对乳液粘度的影响,并就羟基含量、n(-NCO)/n(-OH)比值(R值)以及纳米碳酸钙的含量等对胶膜的耐水性能和粘接强度的影响进行了研究。研究结果表明:PVA含量为1.5%～2.5%时乳液粘度比较适宜;当R值为1.3、羟基含量为2%～3%及纳米碳酸钙加入量为2%～3%时,胶膜综合性能优异。     

乙烯基三乙氧基硅烷/丙烯酸酯共聚乳液的研究

以聚丙烯酸丁酯为种子乳液，将乙烯基三乙氧基硅烷（VTES）与丙烯酸酯进行乳液共聚，制成了聚合稳定性良好，性能稳定的有机硅／丙烯酸酯共聚乳液，详细讨论了VTES用量对聚合过程稳定性和乳液粒径大小及分布的影响，采用动态光散射法跟踪了聚合过程的粒径大小及分布，采用TEM表征了粒子形态；同时研究了乳液的粘度及乳胶膜的耐水性能，结果表明：乳胶粒的平均粒径随聚合时间的延长逐渐增大，乳胶粒呈球形，具有核壳结构，随着VTES用量的增加，乳液聚合的稳定性变差，乳胶粒的平均粒均增大，乳液的粘度增加，乳胶膜的吸水率减小。     

Synthesis of ambient temperature self-crosslinking VTES-based core–shell polyacrylate emulsion via modified micro-emulsion polymerization process

Modified micro-emulsion polymerization was successfully used to synthesize a kind of ambient temperature self-crosslinking core–shell emulsion, consisting of polyacrylate core and vinyltriethoxysilane (VTES) modified polyacrylate shell, by varying the ratio of soft monomer (BA) and hard monomer (MMA) which is different in the core and shell. The emulsion and its film formed at ambient temperature were characterized by attenuated total reflectance-fourier transform infrared spectroscopy (ATR-FTIR), transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Core–shell structure was clearly shown in TEM micrographs, and two distinct glass transition temperatures (T _g) were confirmed by DSC analysis. Lower T _g of core phase analyzed by DSC and self-crosslinking properties of VTES characterized by crosslinking degree cause latex particles form continuous film at ambient temperature. Thermal and mechanical properties and the surface properties of the latex films were also investigated. Results showed that the core–shell latex films containing 5 and 7.5 % VTES exhibited higher thermal stability, better mechanical properties, higher contact angle, and water resistance compared with pure polyacrylate film.     

含磷丙烯酸酯乳液的制备及性能研究

以甲基丙烯酸酯基烷氧基磷酸酯（PAM-100）、甲基丙烯酸甲酯、丙烯酸丁酯、丙烯酸等为单体,采用预乳化半连续乳液聚合法制备了含磷丙烯酸酯共聚乳液。研究了PAM-100用量对单体转化率、乳液稳定性和乳胶粒粒径及分布的影响,并通过红外光谱（FT-IR）和微型燃烧量热分析（MCC）对乳胶膜的结构及性能进行表征。结果表明：PAM-100的加入有利于提高乳液聚合的稳定性及乳胶膜阻燃性能。与纯丙乳液相比,当PAM-100用量为10wt%时,含磷丙烯酸酯共聚乳液的乳胶粒表面Zeta电位绝对值由34.6mV提高至41.3mV,粒径由169nm下降至132nm;同时,含磷丙烯酸酯乳胶膜热释放速率峰值（pHRR）由391.1W/g下降至333.3W/g,到达pHRR的时间由264s推迟至300s。     

Synthesis and characterization of polyacrylate latex containing fluorine and silicon via semi-continuous seeded emulsion polymerization

The polyacrylate latex containing fluorine and silicon were successfully synthesized by semi-continuous seeded emulsion polymerization in the presence of the mixed emulsifier of novel sodium lauroyl glutamate (SLG) anion surfactant and BCE-10 nonionic surfactant, which methyl methacrylate (MMA) and butyl acrylate (BA) were used as main monomers and hexafluorobutyl methacrylate (HFMA) and vinyltriethoxysilane (VTES) were used as the functional monomers. Potassium persulfate (KPS) was used as the initiator. The structural groups of the latex films were evaluated by Fourier transform infrared spectroscopy (FTIR). Thermal performance of the film was evaluated by differential scanning calorimetry (DSC) and thermogravimetric analysis. The latex particle size and its distribution were measured by the dynamic light scattering detector. Furthermore, surface hydrophobicity of the latex film was examined by measurement of water contact angle (WCA). WCA and thermal stability of the film are increased with the increased amount of HFMA and VTES. Factors, which have an influence on the properties of the resultant latex and its film, are investigated in detail. Results show that the optimal condition of synthesizing the emulsion is as follows: the amount of emulsifiers is 7.0%; mass ratio of SLG to BCE-10 is 1:1; the amount of initiator is 0.8%; the mass ratio of MMA to BA is 1:1; the content of the fluorine monomer and silicon monomer is 6.0%.     

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。     

核壳型聚丙烯酸酯乳液的耐水性能研究

采用种子乳液二阶段聚合法,制备了经丙烯酸(AA)/丙烯酰胺(AM)交联、具有核壳结构的甲基丙烯酸甲酯(MMA)/丙烯酸丁酯(BA)/丙烯腈(AN)复合乳液,研究了核壳软硬单体比、AN及壳层中交联单体AM含量对乳胶膜吸水率的影响。结果表明:乳胶膜吸水率主要受壳层软硬单体比例的影响,软硬单体比值越小,乳胶膜的吸水率越低;丙烯酸/丙烯酰胺复合交联剂对乳胶膜吸水率的影响不明显;功能单体丙烯腈可明显降低乳胶膜的吸水率,乳胶膜吸水率随丙烯腈含量的增加而逐渐降低,最低达到9.40%。     

硅丙乳液的合成及其吸水性的研究

以丙烯酸丁酯、甲基丙烯酸甲酯、丙烯酸、乙烯基三乙氧基硅烷(VTES)为原料,分别采用半连续法、种子预乳化法和后添加VTES法制得了硅丙乳液。研究了聚合工艺对硅丙乳液的吸水率、冻融稳定性、钙离子稳定性等的影响。结果表明,采用半连续法和种子预乳化法制得的硅丙乳液,冻融稳定性比较好,经过冻融循环后可以复原;采用半连续法制得的乳胶膜的吸水率随着乙烯基三乙氧基硅烷的用量的增加而降低;采用后添加VTES法制得的硅丙乳液,其吸水率则随VTES用量的增加而升高,冻融循环后发生破乳。     

Surface immobilisation of fluorinated polystyrene‐acrylate latex nanoparticles with core–shell structure by crosslinking

Fluorinated polystyrene‐acrylate (PSA) latex nanoparticles with core–shell structure were synthesised by two‐stage seeded emulsion polymerisation method in the presence of reactive emulsifier DNS‐86. Diallyl phthalate (DAP) and Vinyltriethoxysilicone (VTES) were used as crosslinking agent to immobilise the fluorinated copolymer on the surface of the latex film. Fourier transform infrared spectroscopy (FTIR) spectra show that fluorine and siloxane monomers were effectively involved in the emulsion copolymerisation. Transmission electron microscope (TEM) observation shows that the prepared emulsion particles had a core–shell structure with fluorinated copolymer in the shell. X‐ray photoelectron spectroscopy (XPS) analysis reveals that fluorine atom has the tendency of migrating to the film–air interface and the incorporation of VTES helps the migration of fluorine atom towards the film–air interface. Water contact angle (WCA) test proved that DAP and VTES as crosslinking agent can immobilise the fluorinated copolymer on the surface of the latex films. © 2011 Canadian Society for Chemical Engineering     

细乳液聚合制备纳米SiO2／含氟丙烯酸酯复合乳液及其性能研究

采用溶胶-凝胶法,以正硅酸乙酯为前驱物,在丙烯酸酯单体为油相介质中原位生成纳米SiO2粒子,并通过细乳液聚合,制备出纳米Si02／含氟丙烯酸酯复合乳液。研究了含氟单体和SiO2的用量对复合乳胶膜性能的影响,并采用FT-IR,DSL等分析手段对产物进行了表征。结果表明：该乳液具有良好的稳定性,粒径分布较窄。当（甲基丙烯酸十二氟庚酯）FA与SiO2的用量分别为6％和5．5％时,乳胶膜表现出良好的疏水性能,对水的接触角达到了102．7°,吸水性降低到6．9％。     

有机硅改性聚丙烯酸酯粘合剂的合成及性能表征

以过硫酸钾(KPS)为引发剂、苯乙烯(ST)为硬单体、丙烯酸异辛酯(EHA)和丙烯酸丁酯(BA)为软单体、丙烯酸(AA)为功能单体,端乙烯基硅油为有机硅改性剂,制备了有机硅改性聚丙烯酸酯乳液;并将其作为粘合剂配成印花色浆,应用于棉织物的涂料印花中。研究了端乙烯基硅油用量对乳液聚合反应、乳胶膜性能及印花色浆的印花性能的影响,并对有机硅改性聚丙烯酸酯乳液进行了红外光谱及电镜表征。结果表明,端乙烯基硅油用量为单体总质量的6.5%时,乳液外观、胶膜性能及印花性能都较好。