胺化改性木质素合成聚氨酯胶粘剂的研究

采用Mannich法对纯化木质素进行胺化改性,以提高其活泼氢数量和木质素的反应活性;然后以此作为部分聚乙二醇的替代物,将其与异氰酸酯反应合成PU(聚氨酯)胶粘剂。结果表明:胺化木质素中引入的氮含量约为2.64%,说明木质素的活性明显提高;当w(胺化木质素)=25%时,相应PU胶粘剂的湿胶接强度(1.53 MPa)达到GB/T 9846—2004标准中Ⅰ类胶合板的指标要求,并且其热稳定性能得以明显提高;胺化木质素可以取代部分聚乙二醇,其含量对胶粘剂的力学性能和热稳定性能影响显著。     

木质素网状聚氨酯泡沫的制备及初步应用

介绍了木质素网状聚氨酯泡沫的制备方法,着重讨论了溶剂对木质素在聚氨酯基体中分布的影响、木质素对聚氨酯软质泡沫的泡孔和力学性能的影响。实验结果表明:木质素的加入可以提高聚氨酯软质泡沫的开孔率,当木质素的质量分数在2%时,可使网化泡沫拉伸强度最高达0.12MPa;当木质素的质量分数在5%时,可使网化泡沫伸长率最高达374.3%;木质素质量分数为5%和8%的聚氨酯软质泡沫经过30d的挂膜测试,最终挂膜量分别达10000mg/L和12100mg/L,可以作为污水处理填料使用。     

Multiphase materials with lignin: 9. Effect of lignin content on interpenetrating polymer network properties

A series of lignin-based polyurethane/poly(methyl methacrylate) (LPU/PMMA) interpenetrating polymer networks (IPNs) were prepared by solvent casting in film form. While the LPU/PMMA ratio remained constant (1:1), the properties of the LPU were controlled by varying the composition of the hydroxypropyl lignin polyol via chain extension with propylene oxide. An increase in the lignin content of the polyol resulted in a decrease in the molecular weight between crosslinks (M_c) and change in the morphology of the LPU/PMMA composite. This effect resulted in the transition from a two-phase material to a single-phase material when the (true) lignin content of the composite rose above 25 wt%. As the lignin content increased, the strength properties of the composites increased. The dynamic mechanical, thermal and ultimate mechanical properties of the entire series of IPNs could be explained by dual phase continuity.     

Preparation and colloidal properties of an aqueous acetic acid lignin containing polyurethane surfactant

Aqueous acetic acid lignin containing polyurethane (ALPU) surfactants were prepared by the replacement of some hydrophobic poly(caprolactone diol) with different concentrations of multifunctional acetic acid lignin (AL), and with dimethylol propionic acid as the hydrophilic segment. The infrared spectra, together with thermogravimetric analysis, demonstrated the presence of AL in the polyurethane (PU) chains. In addition, the effects of the AL concentration on the particle size, morphology, rheological behavior, and surface activity of the dispersions were investigated. The ALPU particles displayed a spherical morphology. With increasing AL concentration from 0 to 10 wt %, the particle size increased from 36 to 260 nm, and the unimodal distribution was detected for ALPU₁₀ with a 10 wt % AL addition. The viscosity and shear‐thinning behavior of the ALPU dispersions decreased, and the lowest surface tension and critical micelle concentration (cmc) were detected for ALPU₁₀. However, when the AL concentration was 15 wt % (ALPU₁₅), the surface tension and cmc increased. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1855–1862, 2013     

酶解玉米秸秆残渣制备聚氨酯硬质泡沫

以制备纤维乙醇得到的酶解玉米秸秆残渣为原料,采用碱性乙醇法提取木质素,然后用聚乙二醇/甘油溶液将木质素进行液化得到木质素基多元醇,并以此液化产物代替部分聚醚多元醇用于聚氨酯泡沫的合成。结果表明:碱性乙醇法得到的木质素提取率为93.5%,木质素质量分数达到94.1%;在PEG-400/丙三醇液化体系中,木质素液化率高达99.5%,液化产物羟值为360 mg KOH/g;在聚氨酯合成中,木质素液化溶液对聚醚多元醇的替代量可以达质量分数47%,所得聚氨酯泡沫产品的芯密度和压缩强度分别为48.6 kg/m3和212 k Pa,满足工业聚氨酯硬泡的国家标准。     

酸性可溶木质素胺的合成及其乳化性能研究

以碱木质素、甲醛和二乙烯三胺（DETA）为原料经过Mannich反应制备木质素胺。采用元素分析、红外光谱和核磁共振等方法对木质素胺的结构进行了表征，并分析了其溶解性能和乳化性能。红外光谱和核磁共振氢谱分析证明了DETA被成功地接枝到木质素的苯环上。合成条件优化时发现反应温度和反应时间对枝接率影响较小，而原料比的影响较大，在温度为80℃、反应时间6 h、甲醛和DETA物质的量比值为3.0、DETA和木质素质量比值为1.55条件下，木质素胺的含氮量最高可达16.95%。同时性能测试结果表明：木质素胺在酸性水溶液中的溶解性与其接枝率有明显的相关性，当木质素胺的含氮量达到16.59%以上时，其在酸性条件下的溶解性达到100%。将木质素胺制备成质量分数为5%、pH值为2的酸性皂液，并制备含固体62%的乳化沥青，经检测，木质素胺的酸性水溶性越好，其乳化沥青性能也越好；当木质素胺的含氮量达到16.95%，乳化沥青的筛上剩余量为0，1 d和5 d贮存稳定性分别小于1%和5%，颗粒的平均粒径均达到2.2 μm。     

木质素聚氨酯薄膜合成条件及性能的研究

以麦草碱木质素、相对分子质量为300和 1000 的聚乙二醇(PEG)及多苯基甲烷多异氰酸酯(PAPI)为原料,以N,N-二甲基甲酰胺为溶剂,使用溶液浇注法固化成型工艺,制备了碱木质素聚氨酯薄膜。通过调整PEG1000与PEG300的比例提高了聚氨酯的力学性能。测定了木质素聚氨酯薄膜的弹性模量、拉伸强度和断裂拉伸率、耐撕裂度。实验结果表明,调节不同相对分子质量聚乙二醇在反应体系中的比例,可以显著提高成膜后的耐撕裂性能,改善由于加入木质素后聚氨酯薄膜过脆的缺点。当使用PEG1000与PEG300物质的量之比值为2.0,异氰酸酯指数为2.5,木质素加入量为 20%(质量分数)时,聚氨酯薄膜的弹性模量为 1.49 GPa、拉伸强度为 36.5 MPa、断裂拉伸率为 12.7%,耐撕裂度为 8460 mN,且成膜性能良好。     

新型紫外线固化环氧树脂/丙烯酸酯改性水性聚氨酯的合成与性能

合成了一种新型的具有高交联密度和优异涂膜性能的环氧树脂和丙烯酸酯同时改性的紫外线（UV）固化水性聚氨酯（UV-EP-AC-WPUD）。通过环氧基团与以异氰酸酯基团（-N=C=O）封端的聚氨酯预聚体之间的反应引入质量分数为4%的环氧树脂E-20。同时,通过聚氨酯链的-N=C=O与二元丙烯酸酯（PEDA）以及季戊四醇三丙烯酸酯（PETA）的羟基之间的反应引入碳碳双键（C=C）,C=C的含量达到4.65 meq·g-1。 质量分数为3%的光引发剂Irgacure 2959被用于引发涂膜中C=C的聚合,涂膜的凝胶含量在12 s UV辐射之后达到91%,意味着C=C的聚合和交联速度快,同时所得到的涂膜的交联度非常高,不溶于溶剂丙酮,测试表明环氧树脂和两种丙烯酸酯单体已经成功嵌入聚氨酯链中,涂膜具有优异的力学性能和化学性能。     

木质素筛余物对物料黏度及聚氨酯合成革剥离强度的影响

木质素是聚氨酯合成革中优良的填充剂,其赋予了聚氨酯合成革特殊的物理性能和加工性能,可降低成本。不同的木质素筛余物对木质素/聚氨酯共混体的黏度及聚氨酯合成革的剥离强度有一定的影响,当木质素筛余物质量分数控制在5.5%～6.5%,能得到较佳的作用效果。     

季铵型木质素/PVA复合树脂的制备

利用木质素为原料,经酚化、胺化改性后,以戊二醛为交联剂,聚乙烯醇(PVA)为载体,合成了季铵型木质素/PVA复合阴离子交换树脂。通过傅里叶红外光谱和扫描电镜对其进行了表征,由正交实验确定了胺化改性的优化条件,并且初步探讨了其改性机理。结果表明:NaOH浓度4mol/L、反应温度70℃、季铵盐单体体积用量20%、反应时间2h为木质素胺化改性的最佳条件。在优化条件下制得该树脂的阴离子交换容量为0.89mmol/g。     

Performance properties of self-curing aqueous-based PU system with tri-glycidyl phosphate curing agent

Amino-terminated and carboxylic acid containing aqueous-based polyurethane (PU) dispersion was prepared by a conventional NCO-terminated PU prepolymer process by using isophorone diisocyanate (IPDI), polypropylene glycol-2000 (PPG-2000) and 2,2′-dimethylolpropanoic acid (DMPA) as the key raw materials. A new curing agent, tri-glycidyl phosphate (POG) was prepared from a substitution reaction of phosphorus oxychloride and glycidol. A single-component self-curable aqueous-based PU system is obtained from an addition of POG into aqueous-base PU dispersion and its curing reaction occurred among POG oxiranes and PU amino groups immediately after hydrophobic POG diffused into PU particles (as polymeric micelles). The cross-linked PU resins were resulted on drying at ambient temperature. Original PU dissolved into THF and ethanol. And its gel content increased to 90.1% and sample loss in ethanol decreased to 9.2% of this self-cured PU system with 5.0 phr POG. The limiting oxygen index (LOI) value is 20 of original PU and its LOI reached to 27 of this same self-cured PU system. The improved mechanical and thermal properties of those self-cured PU resins were evaluated, respectively in this report.     

聚氨酯增韧环氧灌封材料的制备与表征

以异氰酸酯封端的聚氨酯预聚体（PU）与环氧树脂（EP）发生反应,制备了聚氨酯接枝改性环氧灌封材料。FTIR表明异氰酸酯封端的聚氨酯预聚体与环氧树脂中的仲羟基完全反应,同时考察了活性稀释剂用量对树脂黏度的影响及固化过程中温度的变化。聚氨酯预聚体的加入,使材料的冲击强度和弯曲强度都有所升高,当聚氨酯质量分数为5％时,材料的弯曲强度提高了30%,而冲击强度提高了近200%,玻璃化转变温度没有降低,SEM分析了其增韧机理。     

木质素胺的制备及其在重金属废水处理中的应用研究

以木质素、甲醛为原料分别与乙二胺、二乙烯三胺、三乙烯四胺通过Mannich反应合成三种木质素胺,考察了吸附时间、温度、pH等吸附条件对废水中铅(Ⅱ)和铬(Ⅵ)吸附效果的影响。实验结果表明:随着温度的升高、pH值的增大、时间的延长,铅(Ⅱ)和铬(Ⅵ)的去除率都增大。铅(Ⅱ)的去除率随着胺基的引入增多而增大,铬(Ⅵ)的去除率没有随着胺基引入增多而增大。     

Effect of silicon and phosphorus on the degradation of polyurethanes

A series of polyurethanes containing silicon and phosphorus was prepared from 4,4′‐diphenylmethane diisocyanate (MDI), poly(tetramethylene ether glycol) (PTMG), diphenylsilanediol (DSiD), and methylphosponic acid (MPA). ¹H‐NMR spectra determined the qualitative and quantitative characteristics of these polymers. The thermal stability and activation energy for thermal degradation of these polymers were measured by thermogravimtry and compared with pure polyurethane (PU). The DSiD incorporated into the main chain of the polymer improved the thermal stability of PU, while the phosphorus‐containing polyurethane (P–PU) displayed a lower thermal stability than that of pure PU. The activation energies at various degradation stages for the pure PU, silicon‐containing polyurethane (Si–PU), and P–PU polymers were calculated by the Ozawa method. The activation energies of the Si–PU polymers were higher than were those of pure PU and increased according to the increase in the DSiD content. However, the P–PU polymers' activation energies were smaller than were those of pure PU, and they decreased with increasing phosphorus content in the range of 0.1 ≤ conversion ≤ 0.5, whereas the reverse was true between 0.6 and 0.9. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 881–899, 2001     

壳聚糖吸附剂的制备及性能

通过以壳聚糖为原料,经交联、羟丙基氯化及胺基化,制备了壳聚糖胺基吸附剂。经红外光谱和扫描电镜测定其结构,研究了不同的胺化试剂及其用量对壳聚糖吸附剂胺基含量的影响及对中药液中黄酮化合物的吸附性能。结果表明,改性壳聚糖微球胺基含量比壳聚糖高,对游离黄酮的吸附量随着胺基含量增加而增加。     

Adsorption of urokinase by polypropylene films with various amine groups

Polypropylene films with various amine groups were prepared by radiation‐induced grafting of glycidyl methacrylate (GMA) onto polypropylene (PP) films and the subsequent amination of poly‐GMA graft chains were examined. The physical and chemical properties of the GMA‐grafted PP film and the aminated PP film were investigated by IR, SEM, XPS, and TGA. The adsorption of urokinase for the PP films modified with various amine groups was examined under various conditions of different amine group contents and pH values. The adsorption of urokinase increased by increasing the amine group content. In the range of amine group content from 1.0 to 2.7 mmol/g, the adsorption of urokinase by the PP films modified with six kinds of amines was in the following order: trimethylamine > diethylenetriamine > triethylenetetraamine > ethylenediamine > dimethylamine > diethyleneamine. The adsorption amounts of urokinase by the PP film with the trimethylamine and triethylenetetraamine groups at pH 7.4 were higher than those at pH 9. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2851–2858, 2001     

戊二醛交联碱木质素/聚乙烯醇膜的制备及其光学性能

以碱木质素和聚乙烯醇(PVA)为原料,以戊二醛为交联剂利用流延法制备了碱木质素/PVA交联反应膜。通过单因素实验考查了碱木质素加入量、戊二醛加入量对木质素／PVA反应膜光学性能的影响。采用SEM和FT-IR方法分析反应膜的表面形貌和化学结构,紫外可见光谱法分析了交联膜的光学性能。结果表明:当碱木质素和聚乙烯醇质量比为1∶10,戊二醛加入量 1.67 %,薄膜的透光率和吸光度都较好。碱木质素/PVA薄膜结构中有醚键生成,碱木质素和PVA发生了交联反应;碱木质素/PVA反应薄膜表面较光滑;加入碱木质素后,薄膜在紫外光区的吸光度提高了近 90 %,在可见光区的透过率降低了近 40 %,碱木质素对薄膜的吸光度和透过率影响较大;戊二醛的加入量增多可见光区透过率有所增大,但戊二醛对薄膜在紫外区吸光度变化不大,薄膜的紫外线吸收主要是受碱木质素的影响。碱木质素/PVA反应膜可作为良好的紫外吸收材料。     

Preparation,properties, and applications of acrylic–polyurethane hybrid emulsions in extinction electrophoresis

Aqueous acrylic–polyurethane hybrid emulsions (PUA) were fabricated by semibatch emulsion copolymerization using a mixture of acrylic (AC) monomers in the presence of an isocyanate terminated polyurethane (PU). The effects of PU content on the morphology of the hybrid emulsions and film properties were here investigated in detail using FT‐IR, UV, TEM, and SEM. TEM images clearly showed that hybrid emulsions exhibited a core‐shell structure before neutralization. However, after neutralization with N,N‐dimethylethanolamine, the typical particles exhibited phase inversion, producing particles with irregular hemispheres shapes and diameters about 0.5 μm. SEM images showed that the film surface became rougher as PU content increased, peaking at 10 wt %, the gloss of this film was 23.1 (60°). The UV transmittance spectra of the PUA hybrid emulsion within a wavelength range 700–200 nm decreased as PU content increased. This was consistent with the changes in the surface roughness of the film. Electrophoresis took place on an aluminum alloy surface and the product was dried at 120°C. The film exhibited excellent mechanical performance due to curing reaction between the N?C?O group on PU and hydroxyl group on the AC copolymer. The gloss of the film was found to be as low as 4.0 after electrophoresis testing. These films may be useful in practical extinction electrophoresis. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40078.     

聚丙烯无纺布预辐射接枝改性及胺化研究

采用丙烯酸(AA)、二乙烯三胺(DETA)依次对聚丙烯(PP)无纺布进行预辐射接枝改性及胺化处理,研究了接枝反应及胺化反应的影响因素,并用红外光谱对产物进行表征。结果表明:随着AA用量的增加,接枝率呈先增长后下降趋势;随着反应温度的升高,反应时间的延长,接枝率增加;随着接枝率的增大,胺化反应温度的升高及反应时间的增加,胺化率增加。接枝反应温度为95℃,25 mL AA与无纺布反应2 h,接枝率可达到276%;接枝率为250%的无纺布与50 mL DETA反应7 h,胺化温度205℃,胺化率可达到73%。红外光谱分析表明,经辐射接枝及胺化处理后的PP无纺布有胺基基团。     

改性木质素泡沫树脂的合成研究

利用稀酸水解木质素、碱木质素为原料,合成了一系列含羟基的木质素聚脂。该树脂经调配,可与异氰酸酯反应制成聚氨酯硬泡材料。实验结果表明:以稀酸水解木质素、碱木质素为原料所制成的木质素多元醇树脂,其粘度为3000～5000 cP·s/20℃,羟值为380～450 mg/g,酸值小于5 mg/g。经调配发泡所制得的硬质泡沫材料,表观密度为0.03～0.05 g/cm³,抗压强度大于0.15MPa,导热系数为0.023 W/(M·K),吸水率3%。性能可达到工业及日常生活对保温的要求。