磁性γ-Fe2O3/P（MMA-AM）纳米复合材料的反相微乳液法制备及表征

以FeSO4.7H2O的水溶液为分散相(水相),环己烷为连续相(油相),甲基丙烯酸甲酯(MMA)和丙烯酰胺(AM)为单体,壬基酚聚氧乙烯醚-10(OP-10)为乳化剂,过硫酸铵(APS)为氧化剂及引发剂,配制反相微乳液体体系。用热引发此体系的反应来制备γ-Fe2O3/P(MMA-AM)纳米磁性复合材料。用X射线衍射、红外光谱、热失重分析、透射电子显微镜对产物进行了表征。结果表明:单体MMA和AM发生了共聚,且γ-Fe2O3微粒分散于高分子聚合物中,则产物为γ-Fe2O3/P(MMA-AM)。制备该磁性复合材料球状微粒的最佳条件为:油水体积比为1∶3、亚铁离子浓度为0.4 mol/L、单体含量为7%(质量分数)。     

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。     

On Interaction between nano-Ag and P(AMPS-co-MMA) copolymer synthesized by ultrasonic

Nano-silver/poly(2-acrylamido-2-methylpropanesulfonic acid (AMPS)-methyl methacrylate (MMA)) [P(AMPS-co-MMA)]composite materials were prepared with the silver nitrate solution containing AMPS and MMA monomers without initiator or reducer, in which Ag⁺ ion was reduced to nanosilver particles and the monomers were copolymerized by ultrasonic simultaneously. The microstructure of the nanocomposite materials was characterized by means of the transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FT-IR), UV-Vis and fluorescence spectrometer. The nanosilver particles were homogeneously dispersed in polymer matrix and the size of particles is in the range of 5~15 nm, the size and distribution of nano silver particles had something to do with ultrasonic time. Spectrum of FT-IR, UV-Vis and fluorescence were indicated that there is chemical action between namo-Ag and special group attached to the copolymer. X-ray photoelectron spectroscopy (XPS) was proved that the interaction between nano silver and the functional group attached to copolymer is of coordination. It is concluded that there is a kind of interaction phenomena of nanometal silver with effective polymer matrix in the nanocomposite materials.     

Synthesis and thermal self-crosslinking reaction of copolymers from 2,3-epoxypropyl methacrylate and p-substituted phenyl methacrylates

Copolymers of 2,3-expoxypropyl (glycidyl) methacrylate (GMA) with various phenyl methacrylates such as 4-nitrophenyl methacrylate (NPMA), 4-chlorophenyl methacrylate (CPMA), or phenyl methacrylate (PMA), and other monomers such as methyl methacrylate (MMA), ethyl acrylate (EA), or styrene (ST) were synthesized by radical copolymerization, and then thermal self-crosslinking reactions of the obtained copolymers were carried out using various catalysts such as quarternary ammonium salts, tert-amines, or the crown ether/potassium salt systems at 100–150°C. Although the copolymer of GMA–NPMA–MMA does not produce any gel products without catalyst upon heating at 110°C for 5 h, this copolymer gives gel products in 82% yield using 10 mol% of tetrabutylammonium bromide as a catalyst under the same conditions. The rate of gel production of the copolymer of NPMA is faster than those of copolymers of CPMA and PMA. The rate of the gel production of the copolymer of GMA–NPMA–EA is also faster than those of copolymers of MMA and ST. Furthermore, it was found that the rate of gel production of the copolymer was strongly affected by the kind of catalyst, the catalyst concentration, and the reaction temperature.     

含氟核壳苯丙乳液的合成与涂膜性能研究

以全氟烷基乙基甲基丙烯酸酯(FMA)为含氟单体、可聚合型烯丙氧基壬基酚聚氧乙烯(10)醚硫酸铵(DNS-86)为乳化剂,采用半连续法制备了具有核壳结构的含氟苯丙乳液。采用FT-IR、TEM、TGA分别对共聚物的组成、乳胶粒形态与涂膜热稳定性进行了表征,并对涂膜接触角及耐化学性进行了分析。结果表明,当FMA用量为8.0%时,所得乳液涂膜的水/油接触角分别为111.5°与67.9°,涂膜的耐化学和热稳定性优良。     

Synthesis of new imidazole-based monomer and copolymerization studies with methyl methacrylate

In this study, copolymers were synthesized using methyl methacrylate (MMA) and 2-allyloxymethyl-1-methylimidazole (AOMMI) monomers at various ratios. For this purpose, hydroxyl end-functionalized imidazole was initially prepared with 1-methylimidazole and then it was used to prepare allyl-derived imidazole monomers. Finally, the synthesis of copolymers (poly(MMA-co-AOMMI)) was carried out using different proportions of commercial MMA and AOMMI monomers. Photopolymerization method was preferred as polymerization technique. The polymerization was carried out in solvent-free medium and benzophenone was used as the initiator. Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR) and elemental analysis were used for the structural characterization of the obtained copolymers. Molecular weights and the thermal behaviour of the synthesized copolymers were analysed with gel permeation chromatography (GPC) and thermogravimetry (TG) techniques, respectively. The surface of the products was tried to be illuminated using scanning electron microscopy (SEM). According to the obtained FTIR, NMR and elemental analysis results, the copolymers were successfully synthesized. A number average molecular weights of poly(MMA-co-AOMMI) samples were found 13,500 (MMA:2/AOMMI:1), 16,600 (MMA:1/AOMMI:2) and 17,300 (MMA:1/AOMMI:1) according to the mixing ratios. When the thermal stabilities of the synthesized copolymers were observed, it has been seen that those containing imidazole had higher stability than the neat PMMA.     

Effect of polyester polyol chain length on the properties of transparent poly (ester-urethane-acrylate)/MMA copolymer for optical applications

A series of poly(ester-urethane acrylate)/methyl methacrylate (PEUMA) crosslinked copolymers were prepared using hydroxyl terminated aromatic polyesters (PEs) with varying chain lengths. Four kinds of PEs with terminal hydroxyl groups were synthesized by reacting phthalic anhydride (PA) with 1,2- propanediol (PDO), 1,4-butanediol (BDO), 1,6-hexanediol (HDO) and diethylene glycol (DEG) respectively. The resultant PEs were reacted with isophorone diisocyanate (IPDI) in the presence of dibutyltin dilaurate (DBTDL) catalyst and end capped with 2-hydroxyethyl methacrylate (HEMA) to obtain ester-urethane-acrylate (EUA) prepolymer. Thereafter, crosslinked PEUMA copolymer were synthesized by reacting the EUA prepolymer with 40% (w/w) methyl methacrylate (MMA) in the presence of 1% azobisisobutyronitrile (AIBN) chain initiator. The PEs and EUA prepolymer were characterized by Fourier transform infrared (FT-IR) spectroscopy, ¹H NMR, and gel permeation chromatography (GPC) techniques. The average molecular weights (Mc) between two crosslinks of the samples were determined by using the Flory Rehner equation. The tensile modulus, flexural strength, thermal properties and transparency of PEUMA copolymers were also determined and correlated with the average molecular weight and crosslinked density. The transparency of PEUMAs was found to be above 90% and hence it is an excellent alternative to glass for optical applications.     

一种含氟共聚物乳液的制备及其性能

通过制备一种含有全氟壬烯基的含氟共聚物乳液,并考察其性能,研究了含氟单体对共聚物乳液性能的影响。以K2S2O8为引发剂,丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)和全氟壬烯基烯丙基醚(PFNAE)为共聚单体,采用半连续乳液聚合的方法,制备了带蓝色荧光的含氟乳液。用傅里叶红外(FT-IR)、接触角、差示量热扫描(DSC)和热重(TG)分析等手段对制备的PFNAE-BA-MMA共聚物(PBM)结构和性能进行表征。结果表明:引入含氟单体后,聚合物的疏水性、热稳定性、玻璃化温度(Tg)都有提高。水在含氟共聚物上的接触角随含氟单体用量的增加而增大,当PFNAE占单体总质量的25%时,水的接触角为94.9°;当PFNAE占单体总质量的20%时,共聚物在221℃开始分解,429.5℃分解完全,该共聚物Tg为8.5℃。PFNAE-BA-MMA共聚物具有一定的拒水性和良好的热稳定性。     

核-壳结构含氟丙烯酸酯乳液的合成与表征

A fluorine-containing polyacrylate copolymer emulsion was synthesized by a seed emulsion polymerization method, in which methyl methacrylate （MMA） and butyl acrylate （BA） were used as main monomers and hexafluorobutyl methacrylate （HFMA） as fluorine-containing monomer. The structure and properties were characterized by Fourier transform infrared spectrum （FT-IR）, transmission electron microscopy （TEM）, particle size analysis, X-ray photoelectron spectroscopy （XPS）, contact angle （CA）, differential scanning calorimetry （DSC） and thermogravimetry （TG） analysis. The FTIR and TEM results showed that HFMA was effectively involved in the emulsion copolymerization, and the formed emulsion particles had a core-shell structure and a narrow particle size distribution. XPS and CA analysis revealed that a gradient concentration of fluorine existed in the depth profile of fluorine-containing emulsion film which was richer in fluorine and more hydrophobic in one side. DSC and TG analysis also showed that a clear core-shell structure existed in the fluorine-containing emulsion particles, and their film showed higher thermal stability than that of fluorine-free emulsion.     

Synthesis and characterization of poly(methyl methacrylate)/polysiloxane composites and their coating properties

A series of poly(methyl methacrylate) (PMMA)/polysiloxane composites and their coatings were prepared as designed. A copolymer (PMMAVTEOS) containing methyl methacrylate (MMA) and vinyltriethoxysilane (VTEOS) was prepared by free radical polymerization and then condensed with methyl triethoxysilane (MTES) to fabricate PMMA/polysiloxane composites; their corresponding coatings were obtained via a curing process in an oven (at 75 °C). The polymers were characterized by gel permeation chromatography and Fourier transform infrared spectroscopy. The surface property, hardness, water contact angle, thermal stability, and optical property of the coatings were investigated by scanning electron microscopy, pencil hardness testing, water contact angle testing, thermogravimetric analysis, and ultraviolet–visible spectroscopy, respectively. The results showed that, after addition of MMA, the pencil hardness of the coatings was reduced from 6H to 2H and the thermal stability decreased from 365 to 314 °C. However, it increased the flexibility and adhesion properties (the water contact angle increased from 94.7° to 102.1°). The transparent PMMA/polysiloxane coatings showed excellent scratch resistance, a smooth surface, high thermal stability, and a strong adhesion property. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46358.     

松香与甲基丙烯酸-β-羟乙酯的酯化反应和加成反应研究

研究了松香与甲基丙烯酸-β-羟乙酯(HEMA)的酯化反应和加成反应,探讨了阻聚剂、催化剂种类和用量、反应温度和原料配比等对酯化反应和加成反应的影响,并采用红外光谱(FT-IR)法和热重分析(TGA)法分别表征了产物的分子结构和酯化物的热稳定性。结果表明:松香分子中的羧基和双键分别与HEMA分子中的羟基和双键发生了酯化反应和加成反应;氧化锌是酯化反应较好的催化剂,当w(氧化锌)=1.0%(相对于松香而言)、反应温度为220℃时,有利于酯化反应的进行;HEMA用量越多,越有利于加成反应的进行;FT-IR表明已成功制取了松香与HEMA的反应产物,TGA表明该产物的热稳定性明显提高。     

Star‐shaped POSS–methacrylate copolymers with phenyl–triazole as terminal groups,synthesis, and the pyrolysis analysis

Star‐shaped polyhedral oligomeric silsesquioxane (POSS)–methacrylate hybrid copolymers with phenyl–triazole as terminal groups had been designed and synthesized via sequential atom transfer radical polymerization (ATRP), azidation, and phenylacetylene‐terminated procedures, and the hybrid copolymers here could be denoted as POSS–(PXMA‐Pytl)₈, where X can be M, B, L, and S, represented four different methacrylate monomers, such as methacrylate (MMA), butyl methacrylate (BMA), lauryl methacrylate (LMA), and stearyl methacrylate (SMA), respectively. Thermal gravimetric analysis (TGA) and in situ Fourier transform infrared spectroscopy (FTIR) were applied for studying the thermal stability and degradation mechanism, and it was found that all of the POSS–(PXMA‐Cl)₈ and POSS–(PXMA‐Pytl)₈ copolymers exhibited excellent thermal stabilities, which had great potential in heat‐resistant material application. Different tendencies of decomposition temperatures at 5% and 10% weight loss (T₅ and T₁₀) dependent on the side‐chain length and terminal group species were investigated respectively. The longer alkyl side chains of the monomers, the lower thermal stabilities, and enhanced T₅ and T₁₀ were also shown with the introduction of phenyl–triazole groups instead of chlorine groups. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40652.     

Effect of methyl methacrylate on the properties of transparent flame retardant unsaturated phosphate ester copolymer

The effect of methyl methacrylate (MMA) on the properties of transparent flame retardant unsaturated phosphate ester copolymer (poly[UPE‐co‐MMA]) prepared by bulk polymerization technique was investigated. Fourier transform infrared spectra, gel fraction (G) test, and dynamic mechanical analysis revealed the structure and crosslinking density of poly(UPE‐co‐MMA) copolymers. The thermal degradation and flame retardancy of copolymers were indicated by thermogravimetric analysis, limiting oxygen index (LOI), and microscale combustion calorimeter (MCC) test. Besides, the mechanical properties and transparency were tested with testing machines and solid ultraviolet absorption spectra. As the MMA content increased to 50%, the copolymer contained 50 wt% MMA showed the maximal G (88.93%) and transmittance was up to 91.72%. From the poly(UPE‐co‐MMA) copolymers, the tensile strength increased from 14.62 to 26.95 MPa, assigned to the increase of crosslinking density of copolymers. The char yield of poly(UPE‐co‐MMA) was up to 21.18 wt%, which was a result of decomposition of phosphate groups, producing a phosphorus‐rich layer that increased the thermal stability of the residues. LOI and MCC results confirm that the introduction of MMA can retain the flame retardancy of copolymer remarkably. POLYM. ENG. SCI., 59:2103–2109, 2019. © 2019 Society of Plastics Engineers     

Synthesis of cassava starch‐g‐poly(methyl methacrylate) copolymers with benzoyl peroxide as an initiator

Graft copolymers of cassava starch and methyl methacrylate (MMA) were synthesized by free‐radical polymerization with benzoyl peroxide (BPO) as an initiator in an aqueous medium at 80°C. The formation of graft copolymers was confirmed by analysis of the obtained products with Fourier transform infrared spectroscopy and scanning electron microscopy. The effects of the amount of cassava starch, the amount of MMA monomer, the amount of BPO, and the reaction time on the grafting characteristics were studied. The optimum condition for grafting were obtained when 5 g of cassava starch, 5 g of MMA, 0.1 g of BPO, and a reaction time of 3 h were used. These condition provided a graft copolymer with 25.00% add‐on, 81.40% monomer conversion, 54.30% homopoly(methyl methacrylate) formed, 45.70% grafting efficiency, 37.20% grafting ratio, and 95.54% yield. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 4083–4089, 2006     

新型含氮反应型阻燃剂的合成与表征

以间苯二甲腈、双氰胺、乙醇胺为原料,以氢氧化钾、乙酸锌为催化剂,在有机溶剂中通过两步反应合成了一种新型含氮反应型阻燃剂—6-[3-(2-噁唑啉基)苯代]-1,3,5-三嗪环-2,4-二胺,产率达84%。采用红外光谱、核磁共振氢谱对其结构进行了表征,并采用热失重分析测试了其热行为。结果表明,该化合物具有较好的热稳定性,700℃时的残炭率为13.23%。     

含氟丙烯酸酯改性聚氨酯核壳乳液的制备及表征

以双键封端水性聚氨酯为反应型高分子,全氟丁基磺酸钾为含氟乳化剂,实现甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、甲基丙烯酸十二氟庚酯(G04)和聚氨酯的共聚,制备具有核壳结构的含氟丙烯酸酯改性聚氨酯乳液(FPUA)。傅里叶变换红外光谱(FTIR)和透射电子显微镜(TEM)对共聚物组成、乳胶粒的形态进行表征,并通过表面接触角、拉伸实验和热重分析等分别研究了FPUA胶膜的表面能、力学性能和热性能。结果表明,当含氟乳化剂和氟单体用量分别为单体总质量的0.15%和20%时,乳液稳定性好,聚合物胶膜表面能由45.6mN/m下降至22.5 mN/m,表现出良好的疏水疏油性,最大热失重速率温度由348℃提高至398℃。     

Graft polymerization of methyl methacrylate onto guar gum with ceric ammonium sulfate/dextrose redox pair

The effect of different reaction conditions on the grafting of methyl methacrylate (MMA) onto guar gum (GG) has been studied in detail. The grafting efficiency was optimal under the following conditions: MMA at 1.13 mol/L; ceric ammonium sulfate at 6.32 × 10^?3 mol/L; dextrose monohydrate at 2.428 × 10^?3 mol/L; GG at 4 g/L; temperature at 50°C; and time at 210 min. Fourier transform infrared spectroscopy was used for the confirmation of copolymer formation. Thermogravimetric analysis of GG and a representative graft copolymer were studied. A probable mechanism of grafting has been suggested. The biodegradability of the resulted copolymer was evaluated. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 3520–3525, 2001     

Preparation and properties of chitosan‐graft‐poly(methyl methacrylate) nanoparticles using potassium diperiodatocuprate (III) as an initiator

Graft copolymer nanoparticles prepared from chitosan (CS) and methyl methacrylate (MMA) monomer were synthesized in aqueous solution by using potassium diperiodatocuprate [Cu(III)] as an initiator and characterized in terms of particle size, zeta potential, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy, thermal stability, and X‐ray diffraction spectrometry. The results indicated that CS was covalently linked to poly(methyl methacrylate) (PMMA), and the resulting copolymers formed nanoparticles. These nanoparticles [prepared at 35°C, in a weight ratio of MMA/CS of 5 : 1 and with a Cu(III) concentration of 1.5 × 10⁻³ mol/L] were 54–350 nm in size, with a mean hydrodynamic diameter of 183 ± 3 nm and were highly uniform in particle‐size distribution, with a rather spherical shape and an obvious positive charge surface. The effect of reaction conditions such as Cu(III) concentration, reaction temperature, and the weight ratio of MMA/CS on the mean particle size was also investigated. Insulin‐loaded nanoparticles were prepared, and their maximal association efficiency was up to 85.41%. The experiment of release in vitro showed that the nanoparticles gave an initial burst release followed by a slowly sustained one. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Alkoxysilane Functionalized Polyurethane/Polysiloxane Copolymers: Synthesis and the Effect of End-Capping Agent

Summary A series of moisture curable polyurethane/polysiloxane (PUSR) copolymers with different end-capping agents were prepared based on amine terminated polysiloxane (PDMS), poly-1,4-butylene adipate glycol (PBA), 4,4′-diphenylmethane diisocyanate (MDI). The copolymers were characterized by Fourier transform infrared (FT-IR) spectroscopy, thermogarvimetric (TGA), X-ray diffraction (XRD), dynamic mechanical thermal analysis (DMTA), X-ray photoelectron spectroscopy (XPS), surface contact angle and stress–strain measurement. Compared with conventional moisture curable PU the PUSR copolymer showed the better thermal stability and surface properties due to the forming of Si-O-Si crosslinking network and the enrichment of siloxane chains on the surface of films , and the tensile strength was not obviously damaged. DMTA results suggested that micro-phase separation was formed in the PUSR copolymer. It was found that the PUSR copolymer with mixed alkoxysilanes as end-capping agents showed better compromised properties than that with single alkoxysilane.     

Synthesis and Characterization of Graft-type MCS Resin

Abstract

MCS resin, formed from methyl methacrylate (MMA), styrene (St), chlorinated polyethylene (CPE), was synthesized by suspension swelling graft-copolymerization. In this paper, the synthesis conditions of MCS, the effect of different synthesis conditions on graft efficiency, the mechanical properties, rheological behavior and morphology were investigated. The graft efficiency increased with increasing CPE content. The apparent viscosity of melt increased with increasing the content of CPE. The copolymer composition was analyzed by FTS-40 Fourier transform infrared spectrometer and PE-2400 element analyzer. The fractured surface morphology of MCS resin was observed by SEM and X-ray energy dispersive spectroscopy.