等离子体及过氧化物引发DT聚合动力学

等离子体引发聚合具有经典自由基聚合不同的特征。文章以碘仿为链转移剂,比较了等离子体及过氧化物引发丙烯酸(AAc)的衰减链转移(DT)聚合动力学。结果表明:碘仿对过氧化物引发体系聚合速率的抑制较等离子体体系明显,同时过氧化物引发DT聚合的分子量更接近于理论值,也更容易在单体转化率较低时得到窄分子量分布(PDI)的聚合物。两种方法引发DT聚合的分子量均与单体转化率呈正比关系,其PDI分别低至1.48、1.64,符合可控/活性聚合的特征。     

高吸盐水型树脂的合成及其影响因素

以(NH4)2S2O8和NaHSO3为氧化还原引发剂,采用水溶液法合成了丙烯酸钠-丙烯酰胺-疏水单体共聚高吸水性树脂.研究了单体聚合浓度、单体含量及引发剂用量等对共聚高吸水树脂吸水率的影响.实验表明,在单体聚合浓度为30%,丙烯酰胺、丙烯酸与疏水单体的质量比为6.7∶9∶1,丙烯酸中和度80%,引发剂用量0.25%时,该聚合物吸水率、耐盐性最好.     

水溶性阳离子聚合物的合成及性能

以甲基丙烯酸二甲胺基乙酯盐酸盐为单体 ,采用低温等离子体引发其水溶液聚合 ,制得了一种水溶性的阳离子聚合物。研究了聚合条件对聚合物产率及特性粘度的影响 ,并研究了聚合物水溶液的流变性能。     

马来酸单酯聚合物复鞣加脂剂的制备与性能

以长链脂肪醇马来酸单酯为亲油单体,丙烯酸为亲水单体,过硫酸铵为引发剂,采用活泼单体滴加方式制备了马来酸单酯聚合物复鞣加脂剂。通过质谱和热重-差热分析对聚合物结构进行了表征。考察了脂肪醇种类,丙烯酸单体滴加速度,单酯与丙烯酸摩尔比和引发剂用量等因素对聚合物性能的影响。结果表明,当脂肪醇为十六醇,n(丙烯酸)/n(单酯)=2.0,过硫酸铵占单体总质量的5%,聚合温度80℃,丙烯酸滴加时间2h时,所得产品具有较好的柔软、填充和防水性能,处理革的增厚率在30%左右,静态吸水率在60%左右。     

丙烯酸类聚合物分散剂的制备

探讨了影响丙烯酸类聚合物分散剂聚合的单体、引发剂、链转移剂以及温度、聚合时间的因素。按照分散剂溶于水后可电离出的分散剂离子的类型,将含丙烯酸的聚合物分散剂进行分类。综述了此类分散剂制备方法和工艺条件。     

无皂乳液聚合制备AANa-VAc-TFEMA纳米含氟乳液

以丙烯酸钠(AANa)、乙酸乙烯酯(VAc)和甲基丙烯酸三氟乙酯(TFEMA)为单体进行无皂乳液聚合,合成了P(AANa-VAc-TFEMA)纳米含氟乳液,考察了反应温度、引发剂用量、单体配比对聚合的影响,并着重对聚合物乳液的粒径进行了研究。结果表明:该聚合单体的转化率可达到97.00%以上,聚合得到的无皂乳液稳定性好、粒径分布均匀。通过控制单体配比中AANa的含量及VAc与TFEMA的比例,可以得到纳米含氟乳液。     

耐盐型高吸水性树脂的合成及性能评价

以氧化还原引发剂(NH4)2S2O8和N aHSO3为引发剂,采用水溶液法合成了丙烯酸钠—丙烯酰胺—疏水单体共聚高吸水性树脂。研究了单体聚合浓度、单体含量及引发剂用量等对共聚高吸水树脂吸水率的影响。实验证明该高吸水聚合物耐盐性较好。     

一种新型丙烯酸类四元共聚破乳剂的合成

以丙烯酸(AA)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)和苯乙烯(ST)为聚合单体,过氧化二苯甲酰(BPO)作引发剂,合成出一种新型丙烯酸类四元共聚破乳剂。考查了各单体配比及引发剂用量对破乳脱水效果的影响。结果表明单体质量比AA∶MMA∶BA∶ST为7∶23∶55∶15,单体总量45 g,引发剂用量1.0 g,合成的聚合物的破乳效果最好。说明丙烯酸类共聚物引入苯乙烯进行改性具有良好的破乳效果。     

反相悬浮法制备淀粉接枝丙烯酸高吸水性树脂

本研究以Span-80自制表面活性剂复配作为分散剂,以过硫酸钾为引发剂引发淀粉接枝丙烯酸进行反向悬浮聚合。详细考察了淀粉/丙烯酸配比、中和度、引发剂用量、交联剂用量等对反向悬浮聚合及接枝聚合物性能的影响。研究结果表明,当淀粉(ST)/丙烯酸(AA)质量比为m(ST):m(AA)=1:3、丙烯酸中和度为75%时、引发剂用量为单体质量的4‰、交联剂用量为单体质量的3‰时,制得的接枝产物表现出最高的吸水倍率,达到1210 g/g。     

阳离子丙烯酸系聚合物乳液的合成和应用

综述了合成阳离子丙烯酸系聚合物乳液的乳化剂、引发剂及单体体系和聚合方法,介绍了阳离子乳液的性质和应用。     

淀粉类高吸水性树脂

淀粉类高吸水性树脂包括淀粉接枝丙烯腈、淀粉接枝丙烯酸、淀粉接枝丙烯酰胺等。它可吸收自身重量几百倍到几千倍的水,保水性好。广泛用于医疗卫生、土建工程、农林等方面。     

水溶液聚合法合成高吸水性树脂的研究

以N,N-亚甲基双丙烯酰胺为交联剂,过硫酸钾-亚硫酸氢钠为引发剂,以丙烯酸和丙烯酰胺为单体,采用水溶液聚合法合成了丙烯酸-丙烯酰胺共聚的吸水树脂,并探讨了单体浓度、单体质量比、丙烯酸中和度、交联剂用量、引发剂用量对吸水树脂吸水量的影响,最大吸水率为799.3 g/g。     

玉米秸秆接枝丙烯酸-丙烯酰胺树脂的制备与吸水性能

以醚化预处理玉米秸秆(PTCS)为基体,丙烯酸(AA)和丙烯酰胺(AM)为单体,过硫酸钾为引发剂,N,N'-亚甲基双丙烯酰胺(MBA)为交联剂,采用水溶液聚合法制备PTCS接枝AA、AM共聚物[PTCS-g-P(AA-co-AM)]。研究了合成条件对树脂吸水率的影响,考察了树脂重复吸水和保水性能,并用红外光谱(FTIR)、电子扫描电镜(SEM)表征了产物的结构和形貌。结果表明,在m(PTCS):m(AA):m(AM)= 1:5:2,丙烯酸中和度为70%,K₂S₂O₈为0.6%,MBA为0.2%,60℃反应3h条件下,制备高吸水性树脂的吸水率最大,对蒸馏水和0.9% NaCl水溶液的吸水率分别为144.04g/g、30.60g/g,且重复吸水和保水性能良好。     

淀粉接枝丙烯酸类超强吸水剂的结构、吸水机理和商业应用

淀粉接枝丙烯酸类超强吸水剂在各个领域的应用越来越广泛。本文简述了淀粉接枝丙烯酸类超强吸水剂的结构和吸水机理，并主要介绍了淀粉接枝丙烯酸类超强吸水剂目前的一些商业应用，包括在生理卫生用品、土木建筑、食品、农业、医药等方面的应用，同时对淀粉接枝丙烯酸类超强吸水剂的发展前景进行了展望。     

壳聚糖接枝聚丙烯酸高吸水树脂的制备及抑菌性能

以壳聚糖和丙烯酸为原料,通过接枝共聚反应合成了具有一定抑菌性能的壳聚糖接枝聚丙烯酸高吸水树脂.研究了引发剂、交联剂、壳聚糖和中和度等因素对树脂吸水性能的影响,探讨了中和度和壳聚糖用量对吸水树脂抑菌率的影响.结果表明,在适宜合成条件下,树脂具有较高的吸水性能及良好的抑菌性能,吸水倍率为684.85 g/g,接枝率为84....     

聚天冬氨酸/聚丙烯酸互穿网络吸水性树脂的制备

以交联聚天冬氨酸(PAsp)、丙烯酸(AAc)为原料,以过硫酸钾为引发剂,以N,N′-亚甲基双丙烯酰胺为交联剂,采用分步法制备了聚天冬氨酸/聚丙烯酸(PAAc)互穿网络吸水性树脂(IPNAP),并对其结构进行了表征,探讨了AAc与PAsp质量比、引发剂用量(以单体质量计,下同)、交联剂用量(以单体质量计,下同)、AAc中和度对IPNAP吸液性能的影响。结果表明,当AAc与PAsp质量比为1.0∶1、引发剂用量为0.50%、交联剂用量为0.40%、AAc中和度为75%时,IPNAP的吸液性能最好,在蒸馏水和生理盐水中的吸液倍率分别达到826g·g-1和120g·g-1。     

Converting date seed biomass into highly absorbing hydrogel

Converting biomass into value-added products has attracted great attention in recent years. In this paper, a facile approach for using date seed powder without delignification is introduced to convert date seed biomass into a water-absorbing polymer. The biomass of date seed as a source of polysaccharides was immersed in the emulsions of acrylic microgels with different chemical structures. Different polymer latexes based on acrylic acid (AA), sodium acrylate (SA), acrylamide (AM) and 2-acrylamide-2-methyl propane sulfonic acid (AMPS) were prepared using inverse emulsion polymerization. A chemical reaction was carried out between date seed and acrylic latex by heating, which caused the conversion of date seed into a semi-synthetic hydrogel with 60 % natural and 40 % synthetic components. The best modification of date seed to absorbing hydrogel was obtained with poly(AA–SA–AM–AMPS). The modified date seed with this latex had water absorbency of up to 71 g/g, while the unmodified date seed had only 0.2 g/g water absorbency. Date seed hydrogels were characterized by Fourier transform infrared spectroscopy (FTIR), dynamic mechanical thermal analysis (DMTA), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), rheometric analysis and swelling measurement. The effect of several modifications of parameters such as latex type, AMPS content in latex, aquatic–organic phase ratios of latex and modification temperature on the swelling properties of hydrogel was investigated. The obtained hybrid hydrogel based on date seed biomass contained a considerable amount of biomass in its structure as well as 71 g/g water absorbency, which can be a proper candidate for agricultural applications.     

接枝共聚法制备高吸水性树脂

以过硫酸钾为引发剂,过硫酸钾与玉米淀粉质量比为0.014,糊化的玉米淀粉与丙烯酸按质量比1:6发生接枝共聚反应,反应温度50℃,反应时间约3.0h,丙烯酸中和度为92%,制得的高吸水性树脂吸收自来水的能力可达560g/g。     

Creating a smart textile via the self‐assembly of responsive polymer particles on poly(ethylene terephthalate) fibers

A novel method is presented for the construction of a hierarchical microstructure/nanostructure via the chemical self‐assembly of poly(N‐isopropyl acrylamide‐co‐acrylic acid) particles on polyester fibers. The textile of the particle‐bound fibers possessed smart wettability and an oil‐absorbing capacity. The wettability was dependent on the initial contact angle and spreading time of water droplets on the particle‐bound textile, which could be controlled with the content of acrylic acid inserted into the polymer chains. The wettability of the particle‐bound textile was responsive to the pH value. In addition, the textile was superoleophilic on an air–solid surface and could absorb oil quickly from water. The oil‐absorbing capacity could be controlled by the alteration of the pH value. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46834.     

Influence of solvent on the poly (acrylic acid)-oligo-(ethylene glycol) polymer gel electrolyte and the performance of quasi-solid-state dye-sensitized solar cells

The influence of solvents on the property of poly (acrylic acid)-oligo-(ethylene glycol) polymer gel electrolyte and photovoltaic performance of quasi-solid-state dye-sensitized solar cells (DSSCs) were investigated. Solvents or mixed solvents with large donor number enhance the liquid electrolyte absorbency, which further influences the ionic conductivity of polymer gel electrolyte. A polymer gel electrolyte with ionic conductivity of 4.45 mS cm⁻¹ was obtained by using poly (acrylic acid)-oligo-(ethylene glycol) as polymer matrix, and absorbing 30 vol.% N-methyl pyrrolidone and 70 vol.% γ-butyrolactone with 0.5 M NaI and 0.05 M I₂. By using this polymer gel electrolyte coupling with 0.4 M pyridine additive, a quasi-solid-state dye-sensitized solar cell with conversion efficiency of 4.74% was obtained under irradiation of 100 mW cm⁻² (AM 1.5).