Acrylate–vinylidene chloride copolymers derived from corresponding water‐borne latexes: Influence of acrylate units on their potential as heavy‐duty anticorrosive coating materials

A series of aqueous latexes with solid contents of 56%–59% were synthesized by binary emulsion copolymerization of vinylidene chloride (VDC) with an acrylate, namely methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), hexyl acrylate (HA), or 2‐ethylhexyl acrylate (EHA). Differential scanning calorimetry (DSC) and Fourier‐transform infrared (FTIR) spectroscopy showed that the acrylate units with short ester side‐chains, such as MA and EA, made the copolymers hard and the crystallization tendency of their PVDC segments was reduced. Hydrophobic acrylates with relatively long ester groups, such as HA and EHA, gave flexible copolymers, and favored the crystallization of their PVDC segments. BA endowed the copolymers with medium flexibility and crystallization tendency. As coating materials, the copolymers bearing MA and EA adhered poorly to the tinplate before or after 100 hr of salt‐spray corrosion, whereas those bearing BA, HA, or EHA showed good adhesion to tinplate when they had little or no crystallinity. After 100 hr of salt‐spray corrosion, only BA–VDC80, containing 80% VDC, retained both excellent adhesion to metal and excellent barrier performance. Further study demonstrated that BA–VDC80 could protect tinplate from rusting for at least 250 hr under harsh salt‐spray corrosion. Scanning electron microscopy, FTIR‐attenuated total reflectance spectroscopy and DSC were used to evaluate the corroded BA–VDC80 film. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40192.     

高性能水性印花涂料的制备

以丙烯酸甲酯(MA)、丙烯酸乙酯(EA)、丙烯酸丁酯(BA)、环氧树脂和乳化剂分别制备核、壳预乳化剂,然后通过种子乳液聚合法制备了具有核壳结构的聚合乳液。以环氧树脂E-44和有机硅氧烷KH-570对聚合乳液进行改性,制备了印花涂料用乳液。研究了乳化剂和核壳单体的配比以及不同改性剂用量对乳液稳定性和成膜性能的影响。结果表明,制备乳液的较佳条件为:复合乳化剂[m(十二烷基硫酸钠)∶m(非离子型乳化剂OS-15)=1∶3]的质量分数为4%,核单体组成为m(MA)∶m(EA)∶m(BA)=1∶1∶3、质量分数为30%～40%,壳单体组成为m(MA)∶m(EA)∶m(BA)=2∶1∶1,改性剂环氧树脂E-44和有机硅氧烷KH-570的用量分别为2%和6%。当烘焙工艺条件为140℃/3min时,制得的印花涂料涂膜在弹性、手感、牢度等性能指标方面均达到了设计要求。     

竹原纤维与丙烯酸酯接枝物的结构与性能研究

以Ce4+引发丙烯酸甲酯(MA)、丙烯酸乙酯(EA)、丙烯酸丁酯(BA)与竹原纤维进行接枝聚合,用ATR、SEM、XRD和TG等手段表征接枝纤维的结构。接枝后纤维强度和初始模量下降,断裂伸长和柔顺性提高;耐酸、耐碱能力随接枝率的增加而提高,热稳定性提高,回潮率下降。接枝单体对纤维的改性效果顺序为BA>EA>MA。     

Azeotropy in terpolymerization of 2-pyrimidyl acrylamide with different alkyl acrylates and acrylonitrile

2-Pyrimidyl acrylamide monomer (2PA) has been prepared by the reaction of 2-amino pyrimidine with acrylolyl chloride in the presence of triethylamine as catalyst. Its structure was confirmed by IR and ¹H NMR spectroscopy. Ternary copolymerizations of 2-pyrimidyl acrylamide monomer (2PA) with methyl acrylate (MA), methyl methacrylate (MMA), ethyl acrylate (EA), butyl acrylate (BuA) and acrylonitrile (AN) were carried out in THF at 65°C in the presence of a free radical initiator. Experimental terpolymerization data agree well with calculations based on the Alfrey–Goldfinger equation. The determination of unitary, binary and ternary azeotropies of the various systems studied were easily handled by a computer. The ternary azeotropic compositions for 2PA–MA–AN and 2PA–MMA–AN were 32.20:17.5:50.30 and 13.54:52.64:33.82mol%, respectively. Pseudo-azeotropic regions were identified where the deviation between feed and polymer composition is very small.     

Studies on the polyblends of poly(vinyl chloride) with various methacrylate copolymers,melt rheological properties. II

Studies have been made on the melt rheological properties of poly(vinyl chloride) (PVC) with copolymers of methyl methacrylate (MMA) and methyl acrylate (MA), ethyl acrylate (EA), butyl acrylate (BA), and 2-ethyl hexyl acrylate (EHA) at a blending ratio of 80:20. Effect of blend composition on shear stress–shear rate, melt viscosity, melt elasticity, and extrudate distortion have been studied. A significant decrease in the melt viscosity is observed on incorporation of low T_g, acrylate copolymers such as those with BA and EHA, thereby reducing the processing temperature. First normal stress and die swell ratio also decreases with an increase in the side chains of acrylate copolymer. PVC blended with P(MMA-co-BA) and P(MMA-co-EHA) is sensitive to both temperature and shear stress.     

Mechanism of the copolymerization of styrene with methyl,ethyl, and n-butyl acrylates in the presence of zinc chloride

The complexes of methyl acrylate (MA), ethyl acrylate (EA) and n-butyl acrylate (BA) with zinc chloride (ZnCl₂) were prepared at 300 K and found to be polar in nature. The viscosity and density of the complexes increased while the tendency to form a binary complex decreased with increase in size of the alkyl substituents of the acrylate monomers. The copolymerization of MA and BA with styrene (Sty) followed a cross-propagation mechanism, whereas the copolymerization of EA with Sty followed a radical-complex mechanism in the presence of their complexes with ZnCl₂.     

Immobilization of Candida lipolytica lipase on macroporous beaded terpolymers with epoxy groups

A series of macroporous beaded terpolymers with epoxy groups were synthesized by suspension polymerization with glycidyl methacrylate (GMA), ethylene glycol dimethacrylate (EGDMA), and the third monomers including styrene, methyl methacrylate, n‐butyl acrylate (BA), butyl methacrylate (BMA), and 2‐hydroxyethyl methacrylate for immobilization of Candida lipolytica lipase. The effect of various third monomers on loading and activity recovery of immobilized lipase were studied. Terpolymers with BA as the third monomer were found to give the biggest loading of lipase, and the activity recovery of lipase immobilized on poly(GMA‐EGDMA‐BA) terpolymers reached 79.0%. As the content of BA (%) increasing, the loading of lipase enhanced, but the activity recovery reached 88.5% for the initial stage and decreased to 46.9% at last. The poly(GMA‐EGDMA‐BA‐10) showed an optimal result in lipase immobilization. Lipase immobilized on poly(GMA‐EGDMA‐BA‐10) carriers had broader pH and higher temperature stability. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Synthesis,characterization, and rheological studies of methacrylic acid–ethyl acrylate–diallyl phthalate copolymers

Copolymerization of methacrylic acid (MAA) and ethyl acrylate (EA) was performed by the emulsion polymerization technique in the presence of a mixture of ionic and nonionic emulsifiers, at 85°C, using potassium persulfate as initiator (0.16 wt % of monomer). The molar ratio of MAA : EA varied between 44 : 56 and 54 : 46 in the monomer feed. Copolymers of MAA and EA were synthesized by incorporating diallyl phthalate (DAP) with varying concentrations (0–1.7 mol % of total monomer) in the feed. A copolymer latex of MAA, EA, and DAP was also prepared by the variable feed process. The intrinsic viscosity and gel content were determined. Copolymers were characterized by IR and NMR spectroscopic techniques. The composition of copolymers was determined by ¹H‐NMR spectra and sequential distribution from ¹³C{¹H}‐NMR spectra. The pH of the copolymer emulsion varied between 3 and 10 by addition of aqueous ammonia (23% w/w) and its effect on Brookfield viscosity was studied. The effects of copolymer composition, crosslinking agent concentration in the feed, monomer feed process, polymer solid contents, and shear rate on Brookfield viscosity were studied at pH ～ 8. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1430–1441, 2003     

Modification of polyvinyl chloride-vinyl acetate latex by seed emulsion polymerization of acrylic monomers

Fundamental studies were carried out to modify the thermal properties of polyvinyl chloride (PVC)-based latices. General features of composite PVC-vinyl acetate (VAc) copolymer latices synthesized from the seed emulsion polymerization of acrylic monomers are reported, in particular, the observation of particle morphology and the measurements of minimum film formation temperature (MFT) and DSC spectra. Acrylic monomers used as modifiers were methyl methacrylate (MMA), n-butyl methacrylate (BMA), methyl acrylate (MA), ethyl acrylate (EA), n-butyl acrylate (nBA), and MMA-nBA 75:25,50:50 and 25:75 wt%. Styrene whose polymer is incompatible with PVC-VAc was used as a counterpart of compatible PMMA. Compatibility between seed and modifier polymer and the mode of operation, either batch (flooded and pre-swollen) or semi-batch (starved and no swelling), induced morphology differences, and consequently variations of thermal properties.     

Effect of ethyleneglycol dimethacrylate crosslinker on the performance of core‐double shell structure poly(vinyl acetate‐butyl acrylate) emulsion

Core‐double shell structure poly(vinyl acetate‐butyl acrylate) emulsion was prepared by semicontinuous emulsion polymerization, and the effects of ethyleneglycol dimethacrylate crosslinker (EGDMA) on the emulsion particle structure and film performance were studied systematically. The emulsion particles' structure was characterized by transmission electron microscopy and Fourier transform infrared spectroscopy, and the particle size and distribution were characterized by Zeta potential—particle analyzer, as well as analysis of the film mechanical properties, water resistance, thermal properties, and so on. The results show that, when 0.1 and 0.5% EGDMA were added to the inner‐shell and outer‐shell reaction stage under the core‐double shell P(VAc‐BA) emulsion preparation process, respectively, it led to a more clear core‐double shell structure and a larger particle size (about 500–800 nm) of emulsion particles, and the comprehensive performance of the P(VAc‐BA) emulsion showed better. This work provided some insight into modifying the surface properties of the emulsion particles, which may expand the application field of the emulsion. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41899.     

新型水处理剂低膦水解聚马来酸酐的合成

以马来酸酐(MA)、双氧水、次磷酸盐为原料,在催化剂的作用下,采用水溶液聚合法,合成出低膦水解聚马来酸酐(HPMA)。合成低膦HPMA的最佳工艺条件为:反应温度110~120℃,反应3 h,催化剂用量为0.05%时,得到固含量为50%的浅黄色透明液体低膦(含磷3%)水解聚马来酸酐。缓蚀阻垢性能研究结果表明,HPMA具有良好的缓蚀、阻垢性能,HPMA药剂浓度为3.0 mg/L时,阻垢率和缓蚀率分别为33.9%和39.38%。     

醇酸交联型丙烯酸酯乳液的制备研究

以丙烯酸丁酯(BA)、丙烯酸甲酯(MA)和丙烯腈(AN)为主要原料,烷基酚聚氧乙烯醚(OP-10)和十二烷基磺酸钠(SDS)为复合乳化剂,过硫酸铵(APS)和亚硫酸氢钠(NaHSO3)为氧化还原型引发剂,采用种子乳液聚合法制备了丙烯酸酯乳液;然后以多元醇A作为丙烯酸酯乳液的交联改性剂,制备了醇酸交联型丙烯酸酯乳液,实现了热交联体系无甲醛化。结果表明:当聚合温度为70℃、w(引发剂)=2.4%、m(BA)∶m(MA)∶m(AN)=33∶11∶6、w(复合乳化剂)=5%且m(OP-10)∶m(SDS)=1∶1.5时,丙烯酸酯乳液的综合性能较好;当n(丙烯酸)∶n(多元醇A)=30∶1、w(丙烯酸)=1.0%时,交联改性乳液的固含量为51.40%、单体转化率为98.3%;交联改性乳液的胶膜吸水率(10.08%)比未改性乳液降低了82.4%,但两者的热稳定性均较高且相差不大。     

Microemulsion Radical Polymerization of Alkyl Acrylates

The oil/water microemulsion polymerizations of alkyl (methyl (MA), ethyl (EA), butyl (BA), hexyl (HA) and 2-ethylhexyl (EHA)) acrylates initiated by a water-soluble (ammonium peroxodisulphate (APS)) initiator were investigated. The rate of polymerization versus conversion curve shows two inconstant intervals. The maximum rate of polymerization of MA, EA, BA and EHA is found to be proportional to the 0·53, 0·17, 0·46 and 0·59 powers of the APS concentration and to the first power of the monomer (MA, BA and EHA) concentration. Homogeneous (solution) radical polymerization is operative in the MA, BA and EHA systems. The strong rate dependence on the EA monomer concentration is assumed to be caused by both the polymerization within the micelle core and the gel effect. The particle size was observed to increase with conversion in the EA and BA runs and to decrease in the EHA and HA runs. The number of particles increased with conversion during the whole polymerization. The polymer particles grow by recruiting monomer and emulsifier from the free monomer-swollen micelles and dead particles. © 1997 SCI.     

Vapor permeation of ethyl acetate,propyl acetate,and butyl acetate with hydrophobic inorganic membrane

This study is focused on the permeation characteristics of ester compounds from aqueous solutions through hydrophobic membrane; ethyl acetate (EA), propyl acetate (PA) and butyl acetate (BA). A surface-modified tube-type alumina membrane (Al₂O₃) was used for ester compounds recovery by vapor permeation. Experiments were performed to evaluate the effects of the feed concentration (0.15–0.60 wt.%) and feed temperature (30–50 °C) on the separation of EA, PA, and BA from dilute aqueous solutions. It was found that the permeation flux increased with increasing feed ester concentration and operating temperature. The fluxes of EA, PA, and BA at 0.60 wt.% feed concentration and 40 °C were 282, 526, 661 g/m² h, which were much higher than those of polymer membranes. The separation factors for the 0.15–0.60 wt.% feed solution of EA, PA, and BA at 40 °C were in the range of 28.1–93.9, 83.6–129.4, and 190.7–209.9, respectively. The membrane tested showed high flux and high selectivity.     

Radiation synthesis of polypropylene-acrylate grafted fiber and its remediation in the spillage of water-insoluble organic chemicals

A new kind of functionalized polypropylene(PP)-acrylate grafted fiber were prepared by radiation-induced graft polymerization of methyl acrylate (MA), ethyl acrylate(EA) and butyl acrylate (BA) monomer onto the PP fiber matrix, as a recovery adsorbent for insoluble organic chemicals. The grafting conditions of monomer concentration and irradiation time on the grafting degree were optimized. The obtained grafted fiber sample was identified by Fourier transform infrared (FT-IR) spectrometer and scanning electron microscopy (SEM) to characterize the chemical and morphological changes of the polypropylene fiber surface. The adsorption results indicated that the grafted fiber could be used to remove organic chemicals from water surface. The adsorption capacity of grafted fiber with different acrylate monomer was obviously different for the same chemicals, therefore, investigations with respect to organic removal, dynamic oil retention, and reusability, the effect of monomer polarity on the adsorption capacity of grafted fiber was especially highlighted in this study.     

新型丙烯酸酯乳液胶粘剂的应用研究

以丙烯酸乙酯(EA)和丙烯酸丁酯(BA)为软单体、甲基丙烯酸甲酯(MMA)为硬单体、甲基丙烯酸(MAA)和丙烯酸(AA)为功能单体,采用种子乳液聚合法制备出一种新型丙烯酸酯乳液胶粘剂。结果表明:当m(EA)∶m(BA)∶m(MMA)=19.2∶6.4∶6.4、m(MAA)∶m(AA)=2.00∶1、w(MAA+AA)=w(BA)=6%～8%以及经氨水中和后胶液的pH为7~8时,该胶粘剂具有良好的综合性能,其初粘强度大、干燥速率快、耐冷藏性能好、不起皱、不掉标且易清洗,完全满足啤酒瓶贴标用胶粘剂的使用要求。     

Poly[N-(2-hydroxypropyl)methacrylamide-block-n-butyl acrylate] micelles in water/DMF mixed solvents

Three diblock copolymers of poly[N-(2-hydroxypropyl)methacrylamide] (poly(HPMA)) and poly(n-butyl acrylate) (poly(BA)) with varying lengths of blocks were prepared by atom transfer radical polymerization. All copolymers were found to be soluble in dimethylformamide (DMF) and poorly soluble or insoluble in water. In water and mixed DMF/H₂O solvents, the copolymers were dispersed in micellar form by controlled addition of water to DMF solutions of copolymers under continuous intensive stirring. The micellar solutions in water were prepared by dialysis of solutions in DMF/H₂O (95 vol% of H₂O) against water. Solution properties of diblock copolymers of poly(HPMA) and poly(BA) were studied using static and dynamic laser light scattering to characterize the behavior of the copolymers at the supramolecular level. The effects of preparation mode, organic solvent (DMF) and copolymer chemical composition on the formation of micelles were studied. While a slower mixing procedure was optimal for copolymers with short poly(HPMA) blocks, a faster mixing was more suitable for copolymers having longer poly(HPMA) blocks. Finally, the dimensions of micelles in water were evaluated. The most compact micelles were prepared from copolymers having short hydrophilic poly(HPMA) blocks. On the other hand, the copolymer with the longest poly(HPMA) block formed micelles with the smallest size and the lowest density.     

水性涂料用苯丙树脂的制备及胶膜性能

以甲基丙烯酸(MAA)为亲水单体、甲基丙烯酸羟丙酯(HPMA)为交联单体,与苯乙烯(St)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)等通过半连续及转相乳液聚合法,制备了具有核壳结构的水性苯丙水分散体乳液,进一步将乳液制备成苯丙树脂胶膜。探讨了MAA核壳质量比,MAA、St、HPMA等单体用量对水性苯丙树脂水分散体乳液性能及胶膜性能的影响,并利用傅里叶变换红外光谱仪(FTIR)及热失重分析仪(TGA)对苯丙树脂胶膜的结构及热稳定性进行了表征,利用激光粒径散射仪(DLS)及透射电镜(TEM)对苯丙树脂乳液乳胶粒的大小及形貌进行了表征。结果表明:当MAA在核壳中分配质量比为2∶8、MAA用量为7%(以单体总质量为基准,下同)、HPMA用量为10%、St与MMA质量比为3∶1时,得到共聚物乳液的粒径为259.65 nm,黏度为349.1 mPa?s,胶膜耐水时间为90 h,硬度为72.4?,拉伸强度为1.422 MPa,断裂伸长率为59.355%;水性苯丙水分散体附着力为1级。     

水性涂料印花黏合剂的合成与性能研究

以丙烯酸异辛酯(2-EHA)、丙烯酸丁酯(BA)、丙烯酸乙酯(EA)、丙烯腈(AN)和丙烯酸(AA)为主要原料,以反应性阴/非离子型乳化剂(HS-10/OP-10)为复合乳化剂、Dow Corning-346为有机硅助剂和甲基丙烯酸缩水甘油酯(GMA)为交联剂,采用半连续滴加预乳液的乳液聚合方法,制备了水性丙烯酸酯类涂料印花黏合剂。探讨了单体、乳化剂和交联剂等对黏合剂性能的影响,并采用红外光谱(FT-IR)法鉴别出国外同类产品中所用助剂的品种及含量。研究结果表明:当m(HS-10)∶m(OP-10)=2.2∶1、w(GMA)=3%、w(BA)=40%、w(2-EHA)=20%、w(EA)=14%、w(AA)=3%、w(AN)=20%和w(Dow Corning-346)=3%时,相应涂料印花黏合剂的综合性能与国外同类产品相当。     

Surface modification of jute yarn by photografting of low‐glass transition temperature monomers

Jute yarns were grafted with three types of vinyl monomers of different functionalities such as methyl acrylate (MA), ethyl acrylate (EA), and 2‐hydroxyethyl acrylate (HEA) with ultraviolet radiation. The graft copolymerization reaction between the cellulose of the jute fibers and the monomer and the chemical environment of the treated fibers were confirmed by Fourier transform infrared spectroscopy. The reduction of OH groups and increment of >C?O groups in treated jute yarns were observed. DSC studies showed that the treated jute fibers were more thermally stable compared to the untreated one. The surface topography of the yarns was analyzed by an environmental scanning electron microscope. Different parameters, such as concentration of monomers and irradiation time, were optimized with the extent of mechanical properties such as tensile strength and elongation at break of the jute yarn. MA, EA, and HEA produced enhanced tensile strengths of 87, 78, and 85%, respectively. The monomers MA, EA, and HEA showed improved elongations at break of 118, 91, and 76%, respectively. The water uptake of treated and untreated jute yarns were studied. The maximum water uptake was observed of the grafted sample compared to the untreated jute yarn. The effects of additives such as urea on mechanical properties were also studied. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 993–1000, 2003