SYNTHESES AND ADSORPTION PROPERTIES OF POLYMER RESINS CONTAINING BENZIDINE AND ITS DERIVATIVES

Three chelating resins were prepared by reacting poly (beta-chloroethyl glycidyl ether) with benzidine, o-tolidine and o-dianisidine respectively, and their structures were confirmed by IR spectra and elementary analyses. The adsorption properties of the resins for Au(III), pd(II), Pt(IV), Hg(II), Cu(II), Pb(II) and Zn(II) were also investigated. The results show that the resin incorporating o-dianisidine exhibits high affinity for Au(III) within a broad range of hydrochloric acid, and selectively sorbs Au(III) in the coexistance of Cu(II), Zn(II) and Mg(II). Desorption of Au(III), Pd(II) and Pt(IV) sorbed proceeded quantitatively using 0.1 mol/l hydrochloric acid containing 2%-10% thiourea as desorbents.

Synthesis and application of a hydrophobic hypercrosslinked polymeric resin for removing VOCs from humid gas stream

A hydrophobic hypercrosslinked polymeric resin LC-1 was prepared and characterized. The properties of LC-1 resin were compared with those of a commercial hypercrosstinked polymer NDA-201 resin. In addition, the dynamic adsorption of trichloroethylene （TCE） onto LC-1 under dry and humid conditions at 303 K was investigated, the result shows that LC-1 possesses high hydrophobic property and can remove TCE from gas stream without effect of high humidity efficiently.

Polymerization of Bisphenol A Epoxy Resin with Polyethylene glycol

The catalyst boron trifluoride etherate was used to catalyze the reaction of epoxy resin with polyethylene glycol (PEG), and the effect of the concentration of the catalyst on the reaction is studied. It is shown that there exist two competitive reactions : I, self polymerization of epoxy resin via chain growth and II, copolymerization of epoxy resin with PEG via step growth. At high concentration of the catalyst reaction I dominates and reaction II is negligible. On the contrary, at low concentration of the catalyst, reaction II dominates and block copolymers are formed In the intermediate case, the two reactions are comparable with the result that a gel structure is obtained.

BINARY COMPETITIVE AND COOPERATIVE ADSORPTION OF AROMATIC COMPOUNDS ON POLYMERIC RESINS

The adsorption behaviors of 2-naphthalenesulfonic acid and aniline on a conventional macroporous resin Amberlite XAD4 and the other two newly-developed hypercrosslinked resins NDA101 and NDAI00 were investigated in a single or binary batch system at 293 K and 313 K, respectively. All the adsorption isotherms of 2-naphthalenesulfonic acid and aniline on the test resins in both systems can fit well with the Langmuir equation, indicating that the adsorption is a favorable process. At the identical equilibrium concentration, the amount of aniline adsorbed on polymeric resins in the single system is higher than that in the binary system because of the competitive adsorption between 2-naphthalenesulfonic acid and aniline on the resin surface. However, the uptake amount of 2-naphthalenesulfonic acid in the binary system is markedly larger than that in the single system, which is presumably due to the cooperative effect arisen from the electrostatic interaction between 2-naphthalenesulfonic acid and aniline adsorbed on the resin surface. The simultaneous adsorption system was proven to be helpful for the selective adsorption toward 2-naphthalenesulfonic acid due to its larger selective index.

STUDY ON POLYMERIZATION OF OILLESS ALKYD RESIN WITH PHENYLTRIETHOXYSILANE

Oilless alkyd resin modified with the silicoorganic compounds has been obtained successfully by polymerization.At appropriate proportion of silicoorganic compounds,the polymerized product has higher hardness and lustre than that of oilless alkyd resin.

Batch Studies for Sorption of Ga(III), Cu(II), Ni(II) and Zn(II) Ions onto Synthetic Polymeric Resins

Poly(acrylamide-acrylic acid-dimethyl amino ethylmethacrylate), p(AM-AA-DMAEM) and Poly(acrylamide-acrylic acid)-ethylene diamine tetracetic acid disodium, p(AM-AA)-EDTANa2 were prepared by gamma radiation-induced template polymerization technique. The prepared polymeric materials were used for the sorption of Ga(III), Cu(II), Ni(II) and Zn(II) in aqueous solution. The effect of pH, weight of resins, metal ion concentrations and contact time on the sorption of these metal ions were studied.

Effect of Zirconium Oxide Nano-Fillers Addition on the Flexural Strength, Fracture Toughness, and Hardness of Heat-Polymerized Acrylic Resin

Purpose: The mechanical strength of polymethyl methacrylate (PMMA) remains far from ideal for maintaining the longevity of denture. The purpose of this study was to evaluate the effect of Zirconium oxide (ZrO2) nanofillers powder with different concentration (1.5%, 3%, 5% and 7%) on the flexural strength, fracture toughness, and hardness of heat-polymerized acrylic resin. Materials and methods: Zirconium oxide powders with different concentrations (1.5%, 3%, 5% and 7%) were incorporated into heat-cure acrylic resin (PMMA) and processed with optimal condition (2.5:1 Powder/monomer ratio, conventional packing method and water bath curing for 2 hours at 95。C) to fabricate test specimens of PMMA of dimensions (50 × 30 × 30 mm) for the flexural strength, fracture toughness, and (50 × 30 × 30 mm) were fabricated for measuring hardness. PMMA without additives was prepared as a test control. Three types of mechanical tests;flexural strength, fracture toughness and hardness were carried out on the samples. The recorded values of flexural strength in (MPa), fracture toughness in (MPa.m1/2), and hardness (VHN) were collected, tabulated and statistically analyzed. One way analysis of variance (ANOVA) and Tukey’s tests were used for testing the significance between the means of tested groups which are statistically significant when the P value ≤ 0.05. Results: Addition of Zirconium oxide nanofillers to PMMA significantly increased the flexural strength, fracture toughness and hardness. Conclusion: These results indicate that Zirconium oxide nanofillers added to PMMA has a potential as a reliable denture base material with increased flexural strength, fracture toughness, and hardness. According to the results of the present study, the best mechanical properties were achieved by adding 7%wt ZrO2 concentration.

Fracture and Tribological Evaluation of Dental Composite Resins Containing Pre-polymerized Particle Fillers

The fracture and tribological evaluation of dental composite resin containing pre-polymerized particle fillers were investigated. Composite resins, e.g. metafil, silux plus, heliomolar and palfique estelite were selected as specimens in order to evaluate the effects of pre-polymerized particle filler on the fracture and wear characteristics of composite resins. In the wear tests, a ball-on-flat wear test method was used. The friction coefficient of metafil was quite high. The wear resistance of silux plus and palfique estelite was better than that of metafil and heliomolar under the same experimental condition. The main wear mechanism of composite resins containing pre-polymerized particle fillers was an abrasive wear by brittle fracture of pre-polymerized particles and by debonding of fillers and matrix.

功能化氮杂环卡宾聚合树脂对Cu^(2+)的吸附研究

该研究制备了功能化氮杂环卡宾聚合树脂(PNO),旨在去除废水中Cu^(2+);基于静态和动态吸附实验,研究了PNO对废水中Cu^(2+)的吸附效果。结果表明:PNO对Cu^(2+)的最佳吸附条件为吸附剂投加量100 mg、吸附时间30 min、pH值4.0~5.9、温度298 K、转速150 r/min,最大吸附量为51.55 mg/g。PNO对Cu^(2+)的吸附过程符合Langmuir、Freundlich等温吸附模型和准二级动力学模型。动态吸附量随柱高增加、流速降低和进水Cu^(2+)浓度增加而增大。使用Thomas和Bohart-Adams模型拟合,相关系数R^(2)均大于0.92,预测值与实验值相符。经过5次静态吸附-解吸和3次动态循环再生后,PNO对Cu^(2+)的去除率仍达到第一次循环的96%以上,去除效果和再生性能良好。PNO对含铜废水高效处理具有广泛的应用前景。

聚丙烯酰胺树脂的反相悬浮聚合制备及吸水性能研究

以丙烯酰胺为单体、过硫酸铵为引发剂、单硬脂酸甘油酯为分散剂、N,N-亚甲基双丙烯酰胺为交联剂,采用反相悬浮聚合法制备了聚丙烯酰胺吸水树脂。考察了分散剂、交联剂、引发剂、单体浓度、油水比、反应温度、反应时间等因素对吸水倍率和产率的影响。结果表明,单硬脂酸甘油酯用量为3%、N,N-亚甲基双丙烯酰胺为0.12%、过硫酸铵为0.5%、单体浓度为30%、油水比范围为4:1~6:1、反应温度在70~75℃、反应时间为4 h时,聚丙烯酰胺树脂的吸水倍率和产率较高。利用傅里叶变换红外光谱仪、热重分析仪和凝胶渗透色谱仪对产物进行了测试表征。

抗菌型高吸水树脂的制备

本文以壳聚糖、丙烯酸为主要原料,先在壳聚糖分子上引入季铵盐侧链,再与丙烯酸钠采用反相悬浮聚合法合成抗菌型高吸水性树脂。并探索了原料的最佳配比,并对吸水性、保水性、抗菌性的影响条件进行了讨论。

双孢菇菇柄高吸水性树脂的制备及其表征

以双孢菇柄多糖、丙烯酸和丙烯酰胺为反应单体,N,N-亚甲基双丙烯酰胺为交联剂,采用水溶液聚合法制备一种新型双孢菇高吸水性树脂。结果表明,双孢菇高吸水性树脂最佳合成工艺为:5 g膨化预处理的菇柄粉加入0.1 g过硫酸钾和20 mL去离子水,丙烯酸添加量6 g,使用前70%中和,丙烯酰胺添加量1.0 g,N,N-亚甲基双丙烯酰胺添加量0.01g,反应温度70℃。20℃条件下,产物双孢菇高吸水性树脂的溶胀率高达474.9 g/g,12小时保水率仍高达78.4%。FT-IR分析结果表明,所有反应物均参与了接枝聚合反应,扫描电镜图像表明膨化双孢菇粉作为反应单体,使得双孢菇高吸水性树脂获得更加疏松多孔的结构。将制备的双孢菇高吸水性树脂作为核心材料,利用其高吸水性,应用于宠物垫料、土壤保水剂和混凝土自养护等领域,实现生物质废弃物的再利用。

壳聚糖增强的桐油聚合物树脂合成及性质

以壳聚糖为原料,利用十二烷基硫酸钠与壳聚糖氨基形成静电复合物,再以含溴活性试剂修饰其羟基,继而将改性桐油基单体通过原子转移自由基聚合接枝到壳聚糖骨架,合成了壳聚糖与桐油的接枝共聚物。选用双马来酰亚胺为交联剂,将壳聚糖接枝共聚物按不同比例混于普通桐油均聚物中,制备出一种具有热可逆键的热固性树脂PTOMA/SCC-g-PTOMA-x。性能研究表明,桐油基聚合物中引入刚性壳聚糖共聚物和交联剂,显著提高了树脂的力学强度,PTOMA/SCC-g-PTOMA-1的拉伸应力高达40.26 MPa。相比于纯桐油基聚合物,PTOMA/SCC-g-PTOMA-0的杨氏模量高达740.5 MPa,说明刚性主链与交联显著提升了树脂的力学性能。研究设计合成了力学性能优良的全生物质可再生树脂,为进一步规模化生产可再生材料提供了思路。

衰减全反射红外光谱法分析本体聚合ABS相转变过程

本体法合成丙烯腈-丁二烯-苯乙烯共聚物(ABS)树脂具有环境友好的优势,然而引发体系以及本体法中的相转变和接枝过程会对ABS成品性能产生影响。采用本体法合成ABS树脂,研究了不同引发剂(偶氮二异丁腈)、链转移剂(叔十二烷基硫醇)、溶剂(乙苯)用量对本体聚合相转变动力学过程和相转变过程的影响。通过衰减全反射-傅里叶变换红外光谱(ATR-FTIR)分析了本体聚合相转变过程中的ABS树脂结构,对比力学性能。结果表明,相转变中的接枝行为会影响聚合速率,适量的引发剂、链转移剂和溶剂(质量分数分别为0.06%,0.30%和20%)有利于相转变过程中的接枝过程,ATR-FTIR分析相转变过程接枝相的苯乙烯的苯环和丙烯腈的腈基峰强度明显增加,同时获得综合性能最佳的ABS树脂。然而链转移剂过量时,ABS中的丙烯腈单体会受到影响。

宽分布聚乙烯管材树脂结构与性能差异性

本文采用高温凝胶渗透色谱(GPC)、差示扫描量热仪(DSC)、万能拉伸试验机、冲击试验机和动态力学分析仪(DMA)等研究了Hostalen(两釜串联)和Hostalen ACP(三釜串联)淤浆聚合工艺制备的宽分布聚乙烯管材树脂GC1和GC2结构与性能的差异性。结果表明,三釜串联生产的GC2平均分子量更大,分子量分布更宽,高分子量级分(重均分子量M_(W)>10^(6))相对含量更高且共聚单体的含量更高。同时,GC2还具有更高的拉伸强度和冲击强度,耐蠕变性能更优异,高剪切速率下具有更好的加工流动性。

有机硅树脂乳液的制备方法及应用研究进展

有机硅树脂乳液是将主链含SiOSi的高度交联聚硅氧烷在外加乳化剂或亲水基团的作用下,经过机械分散后形成的聚合物乳液,具有环境友好特性,可用于水性耐高温涂料、防水涂料、水性胶黏剂、日化和纺织品、纸张及皮革整理等。本文详细综述了有机硅树脂乳液的3种常用制备方法,重点介绍了其应用进展,并对未来发展方向进行了展望。

前线聚合法制备脂肪酸环氧Vitrimer材料的研究

本文研究了不同分子量二元酸改性221环氧树脂对树脂的前线聚合和固化行为的影响。对固化后Vitrimer材料的拉伸性能、热机械动态性能、应力松弛和回收性能进行研究。结果表明,随着二元酸分子量的增加,前线聚合最高温度、推动速率降低、引发时间增加。制备的Vitrimer材料随着二元酸分子量的增加,应力松弛时间增加,且可实现热压和溶剂回收。

间接法Geramage聚合瓷贴面与直接法光固化树脂在活髓前牙美容修复中的疗效对比

目的:探讨间接法Geramage聚合瓷贴面修复体与直接法光固化树脂贴面修复在活髓前牙美容中的应用效果差异。方法:选取2018年6-2021年6月就诊于笔者医院拟实施活髓前牙美容的患者100例(240颗患牙),采用随机数字表法分为研究组和对照组各50例,研究组采用间接法Geramage聚合瓷贴面修复体修复,对照组采用直接法光固化树脂贴面修复,对比两组修复后的菌斑指数(Plaque index,PI)、牙龈指数(Gingival index,GI)、龈沟探诊深度(Probing depth,PD)、龈沟液中白细胞介素-1β(Interleukin-1β,IL-1β)、肿瘤坏死因子-α(Tumor necrosis factor-α,TNF-α)、修复体美学效果。结果:修复后3个月复查,研究组的PI、GI、PD值均显著小于对照组,差异均具有统计学意义(P<0.05);治疗前,研究组和对照组的龈沟液中IL-1β、TNF-α水平差异均无统计学意义(P>0.05);治疗后3个月,研究组的龈沟液中IL-1β、TNF-α水平显著低于对照组,差异具有统计学意义(P<0.05);治疗后12个月,研究组的修复体边缘染色、修复体与邻牙颜色匹配度、修复体边缘适合性达到A级达标率高于对照组(P<0.05),研究组和对照组的修复体完整度、基牙敏感程度及牙髓状态达标率差异无统计学意义(P>0.05)。结论:间接法Geramage聚合瓷贴面修复体在活髓前牙美容中的效果优于直接法光固化树脂贴面修复,且对牙周组织的健康影响更小。

悬浮聚合法制备多孔吡啶基阴离子交换树脂及其表征

采用悬浮聚合法成功制备了多孔吡啶基弱碱性阴离子交换树脂(4VP-DVB),通过季铵化制备了强碱性阴离子交换树脂(4VP-DVBQ)。对两种树脂采用粒径分析、扫描电子显微镜(SEM)、比表面积测试(BET)、傅立叶变换红外吸收光谱(FT IR)以及热重分析(TGA)等进行了表征,并对成本进行了评估。实验结果表明:两种树脂都具有规则的球形结构,粒径分布于40~130μm,具备多孔性结构且平均孔径达15 nm;TGA结果表明,两种树脂有较好的热稳定性能,起始分解温度在200℃以上。

自交联疏水型丙烯酸树脂乳液的制备及性能

制备了封闭单体,并以丙烯酸十八酯(SA)、封闭单体、甲基丙烯酸异冰片酯(IBOMA)为主要原料,十八烷基三甲基氯化铵(1831)和脂肪醇聚氧乙烯醚(AEO-9)为乳化剂,采用乳液聚合方法制备了自交联疏水型丙烯酸树脂乳液。通过红外光谱、粒径、DSC、热重分析等对封闭单体及丙烯酸树脂乳液进行了表征,利用扫描电镜对丙烯酸树脂处理后的织物表面形貌进行了表征,分析了封闭单体解封温度,测定了织物表面的接触角及滚动接触角,研究了封闭单体用量及温度对织物表面丙烯酸树脂疏水性能的影响。结果表明,封闭单体的解封温度为87℃,当封闭单体质量分数为6%时制备的丙烯酸树脂乳液性能稳定,在织物表面接触角可达132.4°,防水性能良好。