室温交联丙烯酸系弹性涂料的研究

本文研究丙烯酸酯类弹性涂料的合成，交联，性能，结构和形态，采用种子乳液聚合，合成了核－壳结构聚合乳液，引入羟基功能单体，调节核层和壳层的组成，以改进和提高弹性涂料所需要的性能，并降低聚合物的玻璃化温度。以多价金属离子为交联剂，使乳液进行室我联。用傅立叶红外光谱对交联乳液进行了结构分析。秀透射电镜和扫描电镜观察核－壳乳液交联后颗粒的形态，并研究交联乳液制成弹性涂料的物理机械性能，获得了一定结果。     

单组分交联型水性聚氨酯

对４种单组分交联型水性聚氨酯的制法及其性能作了评述，这些水性聚氨酯主要属于交联型聚氨酯乳液、热反应型水性聚氨酯。     

交联型聚氨酯／苯丙树脂复合乳液的研究研究

将双丙酮丙烯酰胺（DAAM）参与共聚的苯丙乳液与含有肼基的聚氨酯水分散体混合后,得到了交联型聚氨酯／苯丙树脂复合乳液。研究了DAAM的用量对苯丙乳液的影响,用傅里叶红外光谱和透射电镜证实了酮羰基与肼基之间发生了交联反应。对乳液膜性能的研究结果表明,交联反应提高了乳液膜的耐水性、耐溶剂性、断裂强度、断裂伸长率。     

交联型水性聚氨酯的合成

合成了交联型水性聚氨酯乳液,并就交联剂对聚氨酯乳液性能,机械性能,粘接性能以及耐水,耐溶剂性能的影响进行了测试。     

交联型聚氨酯/苯丙树脂复合乳液的研究

将双丙酮丙烯酰胺 (DAAM)参与共聚的苯丙乳液与含有肼基的聚氨酯水分散体混合后 ,得到了交联型聚氨酯 /苯丙树脂复合乳液。研究了 DAAM的用量对苯丙乳液的影响。用傅里叶红外光谱和透射电镜证实了酮羰基与肼基之间发生了交联反应。对乳液膜性能的研究结果表明 ,交联反应提高了乳液膜的耐水性、耐溶剂性、断裂强度、断裂伸长率。     

交联型硅丙共聚乳液

华南理工大学的周新华等人采用γ -甲基丙烯酰氧基丙基三甲氧基硅烷 (A - 1 74)对丙烯酸酯乳液进行改性 ,得到交联型丙烯酸酯乳液。并对产物进行了红外、DSC、粒径及其分布、混合溶剂不溶解率等测试 ,证实了交联结构的存在。涂膜性能测试表明 ,A - 1 74极大地提高了聚丙烯酸酯的硬度、抗冲击性、耐水性、耐溶剂性和拉伸强度交联型硅丙共聚乳液     

涂布纸涂料用交联型苯丙乳液的制备及应用

以双丙酮丙烯酰胺作为官能单体与其他乙烯基单体共聚,合成了含有酮羰基的苯丙乳液,再与肼混合,制备交联型苯丙乳液,用红外光谱证实了交联反应的发生,并探讨了交联反应对乳液膜性能和涂布纸性能的影响。     

乙烯基有机硅氧烷改性软包装水性复合胶粘剂研究

通过半连续种子乳液聚合工艺,引入交联单体乙烯基三异丙氧基硅烷,本文成功合成了乙烯基有机硅氧烷改性软包装水性丙烯酸酯胶粘剂乳液,并考察了交联单体的加入时间、用量对乳液及胶膜性能的影响。结果表明:各种功能单体、聚合型乳化剂、交联单体均参与了共聚反应,当交联单体在预乳液滴加结束前0.5 h均匀混入预乳液,用量为1.5%时,乳液及胶膜综合性能最优。     

多重交联聚氨酯-丙烯酸酯复合乳液的合成研究

采用种子乳液聚合结合原位乳液聚合法,引入分子间和分子内交联的交联结构,制备了多重交联的聚氨酯-丙烯酸酯复合乳液,研究了交联基团加入方式、用量等对乳液及涂膜性能的影响.研究发现交联度的提高对于涂膜的硬度、耐水性、耐化学品性等有明显改进.     

交联型聚丙烯酸酯乳液的研究

采用半连续法合成了一种交联型聚丙烯酸酯乳液,讨论了交联单体的用量、外加交联剂的用量、固化温度等因素对胶粘剂性能的影响。研究表明,交联单体用量约为8.8%,制得的胶粘剂性能优良;外加4‰的交联剂,在110℃下烘干固化,可显著提高胶粘剂的耐水性。     

室温下丙烯酸酯共聚物乳液的可见光交联研究

在丙烯酸酯共聚物乳液中加入光活性乙烯基不饱和交联单体和与可见光匹配的光敏引发剂共混后涂膜并在室温自然光下固化交联。考察了光敏引发剂用量、交联单体种类和用量、交联时间对乳胶膜交联程度的影响。结果表明以异丙基硫杂蒽酮 ( ITX)为光引发剂 ,分别以甲基丙烯酸缩水甘油酯 ( GMA)、三丙二醇二丙烯酸酯 ( TPGDA)及三羟甲基丙烷三丙烯酸酯 ( TMPTA)为交联单体时 ,2～ 3h乳胶膜交联程度大于5 0 %,8h内交联程度大于 80 %。     

水性环氧丙烯酸酯乳液涂层成膜性能

采用细乳液聚合法制备了环氧丙烯酸酯复合乳液,考察了固化温度、固化时间及磷酸酯乳化剂含量对环氧丙烯酸酯复合涂膜性能的影响,结果表明环氧丙烯酸酯复合乳胶粒子呈均匀的球形结构,且平均粒径分布在150 nm左右。当固化温度为120℃、固化时间为2 h、磷酸酯乳化剂含量为3%时,涂层的耐腐蚀性较好。研究了复合乳液的成膜过程和防腐蚀机理,通过复合乳液与金属底材形成致密的钝化膜,阻隔水分子和无机离子的浸入,提高了涂层的防腐性能。     

Effect of the nature of the crosslinking agent on the metal‐ion complexation characteristics of 4 mol % DVB‐ and NNMBA‐crosslinked polyacrylamide‐supported glycines

Metal‐ion complexation behavior of glycine functions supported on divinylbenzene (DVB)‐ and N,N′‐methylene bisacrylamide (NNMBA)‐crosslinked polyacrylamide was carried out toward Co(II), Ni(II), Cu(II), and Zn(II) ions. The polymeric ligands and the derived metal complexes were characterized by IR, UV, and EPR spectra and by SEM. The metal‐ion complexation of the rigid DVB‐crosslinked system is lower than that of the semirigid NNMBA‐crosslinked system. The glycine ligands renervated after the desorption of the metal ions showed an unusual specificity toward the desorbed metal ion. The low degree of crosslinking makes the desorption process simple and shows fast rebinding kinetics. The metal‐ion‐desorbed polymeric ligands would have pockets or holes characteristic of the desorbed metal ion, resulting in its specific rebinding. The rigidity of the crosslinking also determines the kinetics of metal‐ion rebinding. The specificity and selectivity characteristics of the crosslinked polymeric ligand was found to be increased as the crosslinking agent changes from semirigid NNMBA to rigid and hydrophobic DVB. Thus, copper‐desorbed resins showed an increased specificity toward copper ions and selectively binds copper ions from a mixture of copper and cobalt ions. The metal‐ion specificity and selectivity characteristics of the metal‐ion‐desorbed system is exploited for the concentration of desorbed metal ions from a mixture of metal ions. The resin is amenable for a continuous process and can be regenerated several times. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 74: 3432–3444, 1999     

Synthesis and characterization of urethane/acrylate composite latex

Polyurethane dispersion and urethane/acrylate composite latex were synthesized and characterized by using a particle size analyzer, gel permeation chromatograph (GPC), Fourier transform infrared spectroscopy coupled with attenuated total reflectance (FTIR‐ATR), dynamic mechanical analysis (DMA), and instron test machine. The amount of solvent and dimethylolpropionic acid (DMPA) used during synthesis of polyurethane resin straightway affected the average particle size and stability of aqueous polyurethane dispersion. The particle size of polyurethane dispersion had nothing to do with that of composite latex. FTIR‐ATR analyses displayed both air‐facing and substrate‐facing surfaces, containing more polyurethane component than the average composition. Some crosslinking reactions occurred in preparing urethane/acrylic composite latex, as indicated by FTIR analyses and solvent extraction. DMA demonstrated three glass transitions for the film from composite latex. Instron tests exhibited better film performance properties for the composite latex than for the corresponding blend latex. A possible particle growth mechanism for preparing urethane/acrylate composite latex was proposed. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1620–1628, 2002; DOI 10.1002/app.10526     

Cycloaliphatic epoxide crosslinkable core-shell latexes: A new strategy for waterborne epoxide coatings

New core-shell acrylic latexes designed for crosslinking with cycloaliphatic diepoxides were prepared. The core consisted of methyl methacrylate (MMA), butyl acrylate (BA), 2-hydroxyethyl met hacrylate (HEMA), and the shell MMA, BA, and methacrylic acid (MAA). A strong acid acrylate was incorporated into the shell to catalyze the crosslinking reactions. The diepoxide crosslinker was introduced into the latex formulation via three methods: (1) added with the monomers during the polymerization of the latex, (2) added after the preparation of the latex in an organic solvent, and (3) added as a separate emulsion. The stability of epoxide was shown to be dependent on latex morphology, initiator system, and reaction conditions. Presented at the 77th Annual Meeting of the Federation of Societies for Coatings Technology, on October 18–22, 1999, in Dallas, TX. Department of Polymers & Coatings, Fargo, ND 58105.     

Mechanism of radiation vulcanization of natural rubber latex sensitized by monoacrylates

The mechanism of radiation vulcanization of natural rubber with 2-ethyl hexyl acrylate (2EHA) monomer was investigated using electron spin resonance spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. The primary radicals formed in the arcylate molecule were found to abstract the allylic hydrogens of the polyisoprene. Crossliking may occur through the allylic radicals and/or main chain radicals formed on the polyacrylate. Acrylate was found to concentrate in the rigid regions of the crosslinked rubber indicating heterogeneity and a nonuniform distribution of the acrylate in the latex particles. The addition of the acrylate and the irradiation seems to effect the Brownian motion of the latex particles. Both the viscosity and the NMR peak widths are effected by the irradiation. Addition of 5% 2EHA increases the crosslinking by a factor of 3.6. The thermal stability of the rubber first increases with the dose in the presence of acrylate, but drops at higher doses due to peroxide formation. © 1995 John Wiley & Sons, Inc.     

Preparation and performance in paper coating of silicone‐modified styrene–butyl acrylate copolymer latex

Silicone‐modified styrene–butyl acrylate copolymer latex was synthesized by emulsion copolymerization by using octamethylcyclotetrasiloxane (D₄), styrene, and butyl acrylate as raw materials, potassium persulfate as initiator and propylmethacrylate triethoxysilane (KH‐570) as crosslinking agent. The infrared spectra studies showed that the vinyl monomers were completely copolymerized with D₄. The prepared silicone‐modified copolymer latex with the interpenetrating polymer networks tended to have higher stability, and better toluene and water resistance than styrene–butyl acrylate latex. The glossiness of coated paper was improved with silicone‐modified copolymer latex, and it was at a maximum when D₄ was about 3% of total monomers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 333–336, 2001     

丙烯酸丁酯/VAE互穿聚合物乳液的研究

以互穿聚合物网络(IPN)方法合成丙烯酸丁酯与VAE共聚物乳液。研究了乳化剂、交联剂、溶胀时间、反应时间等条件对转化率的影响。以红外光谱、透射电子显微镜表征互穿共聚物乳胶膜的微观结构。通过吸水性及乳胶膜对水接触角的测定，证明其耐水性较VAE乳胶膜明显增强。。YEM照片表明互穿聚合物胶粒形态结构较VAE乳胶粒发生了明显变化。     

Complex-forming polymeric sorbents with macromolecular arrangement favorable for ion sorption

Crosslinked polymeric sorbents with macromolecular arrangement favorable for sorption of copper ions have been obtained obtained on the base of copolymer of diethyl ester of vinylphosphonic acid with acrylic acid. The general principle involves interaction of linear polymer and sorbing ions in solution where the segments of the macromolecules are still mobile enough, subsequent fixation of optimal ion uptake conformations of macromolecules by crosslinking of metal polymer complexes, and removal of ions from crosslinked sorbent. Such treatment increases the exchange capacity of the sorbents more than twice and improves essentially its kinetic characteristics in comparison with the same copolymer crosslinked by conventional methods without special arrangement of macromolecules. The rate of the uptake on the sorbents with macromolecular arrangement favorable for ion sorption first increases with increase in the degree of crosslinking and then decreases. Apparently the jise of the crosslinking degree leads to more rigid fixation of the optimum ion uptake conformations of the macromolecules' segments. Further increase of the crosslinking degree alongside with fixation prevents ions from diffusion into the sorbent.     

离子液体萃取重金属离子的研究进展

离子液体作为一种新型的绿色溶剂,在重金属离子萃取分离方面较传统的有机溶剂有显著的优势。本文系统综述了近年来使用离子液体萃取重金属离子的研究进展,详细讨论了离子液体萃取重金属离子的原理和影响因素,包括螯合剂浓度、萃取时间、萃取温度、离子液体组成、溶液pH值、金属离子初始浓度、干扰离子以及水/离子液体质量比等。进一步介绍了提高离子液体萃取性能的措施以及金属离子的脱除与离子液体的回收状况,以及该萃取方法在废水处理、重金属离子分析和冶金中的研究与应用现状,最后指出其未来发展方向是合成功能化离子液体、提高萃取效率,以实现其工业化应用。