Preparation and Characterization of Starch/Methylelnebisacrylamide/Dimethylaminoethyl Methacrylate Anion Exchange Composite

Starch/methylenebisacrylamide/dimethylaminoethyl methacrylate anion exchange composite was prepared by polymerizing aqueous mixture of dimethylaminoethyl methacrylate (DMAEMA) / methylenebisacrylamide (MBA) in presence of starch using ammonium peroxydisulphate/sodium thiosulphate redox system. The effects of the concentrations of each of ammonium peroxydisulphate, sodium thiosulphate, MBA and DMAEMA as well as the polymerization temperature on the synthesis were investigated. Polymerization conditions were chosen to prepare an anion exchange composite having amino and MBA-nitrogen contents of 145 and 72 meq/100g, respectively. Potentiometric titration showed that this composite is a weak base anion exchanger of a pK_b of 7. Water solubility and swellability as well as durability of this composite were investigated.     

反应型纸张湿强剂乳液的合成及性能

以苯乙烯、甲基丙烯酸丁酯为主要聚合单体,甲基丙烯酸缩水甘油酯(GMA)为功能单体,十六烷基三甲基氯化铵(1631)、十二烷基硫酸钠(SDS)为乳化剂,分别合成了环境友好型的阳离子型、阴离子型苯乙烯-甲基丙烯酸丁酯-甲基丙烯酸缩水甘油酯(PBG)造纸湿强剂。研究表明:阳离子型乳化剂使PBG聚合物阳离子化,不仅使乳液的转化率相对较高,而且能使纸张的湿强度达到35.68%,同时提高纸张的干抗张强度,且对纸张的撕裂度、耐破度都有一定的增强效果。GMA赋予聚合物乳液环氧基团,与纸张中的纤维形成共价键结合,形成耐水的交联网络,综合考虑价格因素,GMA的用量控制在10%左右即可产生较好的增强效果。     

Radiation-induced graft polymerization of acrylic acid and glycidyl methacrylate onto abaca/polyester nonwoven fabric

Surface modified fibrous materials that possess carboxylic and amine functional groups were developed from a nonwoven fabric (NWF) containing abaca fibers. A facile method was employed for graft polymerization of acrylic acid (AA) and glycidyl methacrylate (GMA) from an electron beam irradiated abaca/polyester NWF. Materials with sufficient amount of graft chains were prepared after reaction of NWF, irradiated at a maximum absorbed dose of 40 kGy, with 15% AA aqueous solution and 5% GMA emulsion for 2 and 3 hours, respectively. Characterization of the pristine, grafted, and functionalized materials with FTIR, TGA, and SEM indicates that grafting and functionalization were successfully performed. The batch adsorption studies showed that the PAA-modified NWF exhibited higher affinity toward Ni²⁺, Cd²⁺, and Pb²⁺ than the EDA-modified abaca/polyester-g-PGMA.     

Poly(Acrylic Acid) Starch Composite as a Substitute for Sodium Alginate in Printing Cotton Fabrics with Reactive Dyes

Poly(acrylic acid)-starch composites were prepared by polymerizing acrylic acid with maize starch using KMnO₄/citric acid as redox initiator system. These composites were used as pastes for printing cotton fabrics with reactive dyes. Results indicate that these composites are of great potential value as thickeners for printing according to the flat screen technique using steam as well as thermal means for dye fixation on the cotton fabric. The colour strength as well as overall fastness properties are comparable, if not superior, to those fabric samples printed using sodium alginate as a thickener.     

Synthesis and Characterization of Starch-N-methylol Acrylamide-Methacrylic Acid Cation Exchange Composites

Starch-N-methylol acrylamide methacrylic acid cation exchange composites were synthesized by polymerizing of highly concentrated aqueous mixtures of methacrylic acid and N-methylol acrylamide with starch using ammonium peroxydisulphate, as an initiator, alone and with different reductants, viz. sodium thiosulphate, sodium pyrosulphite and glucose. Sodium thiosulphate proved to be the best reductant that can produce the composite at the lowest solidification time with the highest insoluble yield and carboxyl content. Factors affecting the process such as temperature, redox system concentration and concentrations of monomers were reported. Four kinds of cation exchange composites, of different nitrogen and carboxyl contents, were prepared. These composites were characterized by potentio-metric titrations, water solubility and swellability, as well as durability to use.     

无皂苯丙乳液制备及表面施胶增强效果研究

以聚乙烯醇和丙酮为分散剂,苯乙烯、丙烯酸丁酯为单体,甲基丙烯酸缩水甘油酯为功能性单体,过硫酸钾为引发剂,采用无皂乳液聚合法合成无皂苯丙乳液.分析结果表明,无皂苯丙乳液胶粒粒径小且分布均匀、分散性好.用乳液浸渍处理纸张,不但具有施胶和增湿强效果,同时也能提高纸张的强度性能和印刷性能.将合成的无皂苯丙乳液与氧化淀粉复配对纸张性能改善的效果比单一使用氧化淀粉的效果好.施胶量较少时,无皂苯丙乳液与氧化淀粉复配不具有施胶和增湿强效果,但可改善纸张强度性能.     

Poly(Acrylic Acid)-Starch Composites. A Key for Improving Sizeability and Desizeability of Starch from Cotton Textiles

Maize and rice starches were independently polymerized with acrylic acid (AA) using potassium permanganate/citric acid initiation system. The dependence of total conversion (grafting and homopolymerization) on AA, potassium permanganate and citric acid concentrations, time and temperature of polymerization and rate of stirring were studied. Based on the results appropriate conditions for preparation of poly(AA)-starch composites were established. While the total conversion increased by increasing AA concentration from 10% to 30%, based on weight of starch (ows), maximum total conversion occured upon using 0,2% potassium permanganate along with 0.025% citric acid, ows, for 10 min at 40°C and stirring rate of 300 r. p. m. It was further disclosed that: (a) the total conversion for maize starch is higher than rice starch, (b) the apparent viscosity of the composite increases by increasing AA concentration from 10% to 30% and polymerization temperature from 30°C to 50°C, (c) for 10% AA concentration the composite consists of 97.67 starch and 2.33% poly-(AA) of which 1.36% is grafted whereas for 30% AA concentration the composite consists of 79.3% starch and 20.7% poly(AA) of which 3.2% is grafted, (d) the sizeability of native starches is considerably improved after polymerization with AA and (e) size removal from cotton fabric with the composites to ca. 80% while wize removal from cotton fabric sized with native starches amounts to ca. 20%.     

经丙烯酸共聚物改性的淀粉糊的流变性能的研究

采用溶液聚合法合成了三元丙烯酸酯共聚物（MA／BA／AA）。红外光谱和X－射线衍射分析了共聚物的组成,并探讨了该共聚物与淀粉反应的过程。结果表明,该共聚物在淀粉颗粒上进行自由基接枝共聚反应,反应主要发生在淀粉颗粒的无定形区,改性后的淀粉能够保持原淀粉颗粒的完整结构。     

丙烯酸接枝淀粉的制备及其印花性能

采用丙烯酸(AA)单体对酸解玉米淀粉进行接枝,讨论了丙烯酸单体与玉米淀粉剩基（AGU）配比、丙烯酸单体pH值、引发剂用量、反应时间及温度对接枝产物接枝率、抱水性及PVID值的影响,并用红外光谱（FTIR）对接枝产物进行表征。试验得出丙烯接枝酸解玉米淀粉优化工艺为：n(AA):n(AGU)=2:1,丙烯酸单体pH值为6、引发剂n(H2O2)/n(FeSO4)=1.98,n(H2O2)=0.529mmol,接枝反应温度为50℃及时间为3h。所得接枝产物接枝率为5.14%,羧基含量为4.02%;接枝产物的抱水性为10.5mm,PVID值为0.34,各项性能与海藻酸钠相近,可作印花原糊用。     

苎麻织物紫外光接枝阻燃改性研究

以甲基丙烯酸缩水甘油酯(GMA)为接枝单体,用紫外光(UV)接枝的方法将GMA接枝到苎麻织物(Pure Ramie)上,接枝后的织物(Ramie-g-GMA)用乙二胺(ED)胺化(Ramie-g-GMA/ED),再用磷酸(OP)磷酸化(Ramie-g-GMA/ED/OP),制得阻燃改性的苎麻。通过热重分析(TGA)、傅立叶红外光谱(FTIR)、扫描电子显微镜(SEM) 和极限氧指数(LOI)等技术和手段研究了阻燃改性前后的苎麻的热降解行为、阻燃性能和结构形貌,并考察了光照时间、引发剂二苯甲酮(BP)浓度、GMA浓度等因素对GMA接枝率的影响。扫描电镜分析和红外光谱研究结果表明GMA接枝到苎麻织物上;GMA接枝率随着光照时间、引发剂浓度和单体浓度的增加而增大;接枝反应20 min、BP浓度为0.3 mol/L、GMA浓度为30 %(v/v)时,GMA接枝率达到35.61 %,织物仍保持很好的手感;磷酸化后的织物在燃烧过程中因磷的催化成炭作用,显著地提高了苎麻织物的阻燃性能;GMA接枝率为50.65%的苎麻织物胺化、磷酸化后LOI可达38.6%。     

MMA/DMC/AM/AA共聚物乳液的合成及其环压增强作用

以丙烯酰胺(AM)、甲基丙烯酰氧乙基三甲基氯化铵(DMC)、甲基丙烯酸甲酯(MMA)和丙烯酸(AA)为主要原料,通过无皂乳液聚合制备了稳定且性能优异的两性MMA/DMC/AM/AA四元共聚物乳液纸张环压增强剂,并优化了合成工艺条件.通过傅里叶红外光谱仪(FT-JR)、热失重分析仪(TGA)、激光颗粒粒度分析仪(DLS)和扫描电镜(SEM)对MMA/DMC/AM/AA四元共聚物乳液纸张环压增强剂结构、胶膜热稳定性、乳液粒径及应用该乳液进行表面施胶前后的纸张进行了分析,并考察了MMA、AM含量和AA与DMC质量比对共聚物乳液环压增强性能的影响.结果表明,w(MMA)=1 5％,w(AM)=8.5％,m(AA)∶m(DMC)=1.5 ～2.0时,制备的共聚物乳液的环压增强性能优异;以共聚物乳液(质量分数为0.5％)和淀粉(质量分数5％)组成的表面施胶液对瓦楞原纸施胶时,施胶后纸张环压指数高达8.68 N·m/g,与施胶前相比提高93.8％.     

Pasting,swelling and solubility properties of UV initiated starch-graft-poly(AA)

UV-initiated graft copolymerization of sago starch with acrylic acid (AA) at low level (2.5%, 5%, 7.5% and 10% w/w) was investigated. The UV curing technique and procedure was found to successfully produce starch-graft-poly(acrylic acid) [S-g-poly(AA)]. The carboxyl group content was found to increase with increasing % of monomer. Rapid visco-analyzer (RVA) pasting profile, swelling and solubility of the samples were studied. UV irradiation of sago starch (control) results in high pasting temperature, high peak viscosity and high setback, besides retarding swelling and solubility as compared to the native untreated starch (p<0.05). Pasting temperature was decreased after grafting as compared to the control. S-g-poly(AA) showed higher peak viscosity, peak time and setback than native untreated starch (p<0.05). Breakdown was retarded at 2.5% S-g-poly(AA) but increased at 10%. S-g-poly(AA) exhibited lower swelling power and solubility than the native sample (p<0.05).     

聚合物乳液在发动机滤纸浸渍剂中的应用研究

本文采用乳液聚合的办法，合成了苯乙烯(Styrene)、丙烯酸丁脂(BA)、丙烯酸(AA)共聚乳液，通过加入交联剂对其进行改性，并将该乳液用做发动机滤纸的浸渍剂。深入地研究了引发剂浓度，复合乳化剂配比及选择对聚合反应过程单体的转化率、乳液粒径及经乳液处理后滤纸的物理机械性能的影响。结果表明，通过交联改性的苯丙乳液在一定工艺条件下，可进一步提高发动机滤纸的物理强度和耐潮性能。     

Gelatinisation Properties of Cassava Starch in the Presence of Salts,Acids and Oxidising Agents

The effect of various cations, anions, acids and oxidising agents on the gelatinisation properties of cassava starch was studied and wide variation was observed in the pasting and swelling properties. Sodium chloride and sodium thiosulphate slightly lowered the peak viscosity of cassava starch with increase in concentration, whereas with sodium sulphite, calcium chloride and sodium hypochlorite, a more significant decrease in the viscosity and breakdown was observed. Ferrous sulphate, alum, aluminium chloride and acids enhanced the peak viscosity at lower concentrations followed by a decrease at 1% and above. Sodium metabisulphite elevated the viscosity at 0.05 and 0.1%, while sodium hypochlorite lowered the viscosity and breakdown. DSC studies showed that aluminium chloride, sodium sulphite, and sodium thiosulphate brought about an increase in T_onset, T_end and ΔH values at higher concentrations. A decrease in swelling volume was observed from 0.05 to 1% concentration of sodium chloride and above that there was a gradual increase. With sodium sulphite, a significant increase in swelling volume was observed at 2.5 and 5% levels. With 0.05 and 0.1% aluminium chloride and sodium metabisulphite an increase in swelling volume was noticed, but at higher concentrations there was a drastic fall. Sodium chloride, sodium sulphite, sodium thiosulphate and calcium chloride brought about decrease in starch paste clarity with increase in salt concentration, whereas ferrous sulphate, aluminium chloride, sodium hypochlorite, hydrochloric acid and acetic acid improved the starch paste clarity.     

交联型两性聚丙烯酸酯的制备及对纸张性能的影响

以聚乙烯醇（PVA）为高分子胶体稳定剂,甲基丙烯酸缩水甘油酯（GMA）为交联剂,丙烯酰胺（AM）、丙烯酸（AA）、丙烯腈（AN）、甲基丙烯酰氧乙基三甲基氯化铵（DMC）为共聚单体,通过无皂乳液共聚制备了交联型两性聚丙烯酸酯表面施胶剂。对阳离子基单体和交联性单体的用量、合成工艺条件等对纸张增强效果的影响进行了探讨。确定了较佳的合成条件：种子聚合法,w（PVA）=3%-4%,w（DMC）=2%-2.5%,w（GMA）=0.7%,反应温度85℃,反应时间5 h。通过差示扫描量热仪（DSC）、扫描电子显微镜（SEM）和粒度分布分析仪对乳液和纸张性能进行了检测与表征。实验证明,在pH值78条件下,以2%的聚合物乳液进行表面施胶时,可使环压指数、耐破度、抗张指数分别达到16.6 N&#183;m/g、440 kPa、40.6 N&#183;m/g,耐折度10次,与空白样相比均可提高30%以上。     

巯基-过硫酸钾表面引发聚合体系的构建及其在羽毛表面接枝的应用

为在羽毛表面引入新的氧化还原表面引发聚合体系,利用巯基乙酸将羽毛中的二硫键还原成巯基,使巯基与溶液中的过硫酸钾构成氧化-还原引发体系,实现油溶性单体甲基丙烯酸缩水甘油酯(GMA)在羽毛表面的引发接枝聚合,制得含环氧基的羽毛接枝共聚物。采用了红外光谱、扫描电镜及热重分析对改性前后的羽毛进行表征。研究了单体浓度、引发剂浓度和反应温度对羽毛表面接枝聚合的影响。研究结果表明:巯基与过硫酸钾可顺利引发GMA在水介质中的接枝聚合;最佳接枝聚合工艺条件为单体浓度0.55 mol/L、引发剂浓度2.6 mmol/L、温度40℃;所制备的羽毛接枝共聚物的接枝率最高可达185.8%;与羽毛相比,热稳定性降低。     

Preparation of Anionic Starch Containing Carboxyl Groups and its Utilization as Chelating Agent

Poly(methyl acrylate)‐starch graft copolymer was treated with sodium hydroxide. The influence of sodium hydroxide concentration, reaction temperature and duration of treatment were studied. The extent of hydrolysis was assessed by estimating acrylic acid, methyl acrylate and total polymer content before and after treatment. It was found that the increase in acrylic acid content is equal to the decrease in the methyl acrylate content on using sodium hydroxide concentration up to 1 N, while using higher concentration leads to a difference in amount of acrylic groups formed and decrease in methyl acrylate content. This difference depended on sodium hydroxide concentration, on treatment temperature and duration. The optimum condition gave a release of 455 mmol acrylic group/100 g sample using 1 N sodium hydroxide at 100 °C for 150 min, showing 94.8% conversion of the poly(methyl acrylate) content of the treated copolymer. The alkali treated samples were evaluated for use as chelating agent. The sorption values for different heavy metals depended on the metal ion and follow the order Hg²⁺ > Cu²⁺ > Zn²⁺ > Pb²⁺ . Sorption efficiency of the alkali treated samples increased with increasing the acrylic content. The sorption values of alkali treated copolymer was compared with that of carboxymethylated starch (having the same carboxy group content) to clarify the effect of the chemical structure of both starch derivatives on heavy metal sorption. It was found that the sorption value of Cu ²⁺ on carboxymethylated starch was twice the value on alkali treated copolymer.     

GMA改性聚丙烯酸酯黏合剂的应用

为了改善涂料印花织物的手感和牢度,探讨用半连续种子乳液聚合的甲基丙烯酸环氧丙酯(GMA)改性的聚丙烯酸酯黏合剂在涂料印花中的应用。研究分析黏合剂用量、黏合剂pH值、焙烘温度和焙烘时间等因素对涂料印花织物干湿摩擦牢度、表观得色量和印花织物手感的影响。结果表明:该黏合剂获得较佳印花效果的应用工艺是其用量为10%,pH值范围为7~8,焙烘温度为150℃,焙烘时间为3 min;与国内外同类产品相比,GMA改性的聚丙烯酸酯黏合剂更能有效增加印花织物的表观得色量,且印花后织物的手感良好。     

反应型乳化剂及丙烯酸十八酯对淀粉接枝苯乙烯-丙烯酸酯阴离子表面施胶剂的影响

通过自由基聚合反应,在氧化淀粉分子链上接枝苯乙烯(St)、丙烯酸丁酯(BA)、丙烯酸十八酯(ODA)、反应型乳化剂DNS-86与甲基丙烯羟丙基磺酸钠(HPMAS),合成一种阴离子淀粉接枝表面施胶剂,探讨反应型乳化剂DNS-86、甲基丙烯羟丙磺酸钠(HPMAS)和丙烯酸十八酯用量对施胶效果的影响。在甲基丙烯酸羟丙基磺酸钠1.5%,丙烯酸十八酯3%,DNS-862%时,合成的阴离子接枝表面施胶剂与氧化淀粉、硫酸铝复配施胶,能够有效提高施胶效果与环压指数。     

氧化降解淀粉与乙烯基单体接枝共聚物复鞣剂的合成及应用研究

经过氧化降解的玉米淀粉与乙烯基单体丙烯酸（AA)和丙烯腈（AN）在Fe^2 -(NH4)2S2O8氧化还原引发剂作用下进行了接枝共聚合反应，制得了改性淀粉复鞣剂。研究了单体浓度及配比、引发剂浓度等因素对接枝共聚合反应的接枝率、单体转化率、接枝效率等的影响，用红外光谱对接枝共聚物的结构进行了分析表征，同时进行了复鞣剂应用实验。