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Hydrolysable Chestnut Tannin Extract Chemical Complexity in Its Reactions for Non-Isocyanate Polyurethanes(nipu)Foams

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Journal of Renewable Materials 2023年第6期11卷 2823-2848页

作者： Elham Azadeh Antonio Pizzi Christine Gerardin-Charbonnier Philippe Gerardin LERMAB Faculty of Science and TechnologyUniversity of LorraineVandoeuvre les Nancy54506France LERMAB University of LorraineEpinal88051France

Non-isocyanate polyurethane(nipu)foams from a commercial hydrolysable tannin extract,chestnut wood tannin extract,have been prepared to determine what chemical species and products are taking part in the reactions *** method is based on two main steps:the reaction with dimethyl carbonate and the formation of urethane bonds by further reaction of the carbonated tannin with a diamine-like hexamethylene *** hydroxyl groups on the tannin polyphenols and on the carbohydrates intimately linked with it and part of a hydrolysable tannin are the groups involved in these *** carbohydrate skeleton of the hydrolysable tannin is also able to participate through its hydroxyl groups to the same two reactions rendering the whole molecular complex able to react to form *** analysis by Matrix-Assisted Laser Desorption Ionization(MALDI-TOF)mass spectrometry and 13C Nuclear Magnetic Resonance(13C NMR)to further investigate the reaction mechanisms involved revealed the unsuspected complexity of chestnut hydrolysable tannin,with different fragments reacting in different manners forming a hardened network of considerable *** the morphology and performance of these types of foams changes slightly with the change in the amount of glutaraldehyde and hexamine hardeners,the best performing foam formulation previously determined was scanned by SEM and analysed chemically for the structures formed.

关键词： Hydrolysable tannin chestnut tannin non-isocyanate bio polyurethanes nipu MALDI-ToF ^(13)C NMR SEM bio-based materials

Effect of Amine Type on Lignin Modification to Evaluate Its Reactivity in Polyol Construction for Non-Isocyanate Polyurethanes(nipu)

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Journal of Renewable Materials 2023年第5期11卷 2171-2190页

作者： Saeed Kazemi Najafi Farhood Najafi Antonio Pizzi Fatemeh Hassani Khorshidi Rabi Behrooz Department of Wood Science and Technology Faculty of Natural ResourcesTarbiat Modares UniversityTehranIran Department of Resin and Additives Institute for Color Science and TechnologyTehranIran LERMAB University of LorraineBlvd des AiguillettesNancyFrance

Polyols are groups of organic compounds which contain carbon and are randomly linked to other atoms,especially carbon-carbon and *** compounds are mainly used as reactants to make other *** biopolymers,lignin is regarded as the base of a new polymer in polyol *** present study aimed to investigate the effects of amine type(diethylenetriamine and ethylenediamine)on the modification of lignin-based polyols,so as to provide an alternative to petroleum polyols and,in turn,increase functional groups and reduce their harm to humans’health and the *** this aim,first,lignin was extracted from raw ***,the extracted lignin was reacted with diethylenetriamine(DETA)and ethylenediamine(EDA).Finally,the Mannich method was used for the reaction between amine lignin and propylene *** results of the Fourier Transform Infrared(FTIR)spectroscopy analysis showed that modification with DETA led to more structural change in lignin and peak 1100 indicates the presence of C–O bond related to urethane bonds in modified ***,adding propylene carbonate to aminated lignin did not result in much change in the results of the FTIR ***,urethane bonds can be seen in the results of GPC at 400℃–500℃.Furthermore,a slight decrease in thermal stability was observed in lignin modified with amine and propylene carbonate,compared to the raw lignin sample.

关键词： Polyol lignin diethylenetriamine ethylenediamine propylene carbonate polyurethanes nipu

Synthesis of bio-based Non-Isocyanate polyurethanes(nipu) with CO2, vegetable oils and amines

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Synthesis of bio-based Non-Isocyanate polyurethanes(NIPU) wi...

Modifying Poly(propylene carbonate) with Furan-based Non-Isocyanate Polyurethanes

中国化学会·第一届全国二氧化碳资源化利用学术会议

作者： Jincheng Dong Jie Yang Xiao Zhang Binyuan Liu Hebei Key Laboratory of Functional Polymer School of Chemical Engineering and TechnologyHebei University of Technology

CO is known as one of the sources of global warming, however it is also an abundant, renewable, non-toxic, inexpensive and environmentally C1 resource. Vegetable oil as a renewable green resource has become a substitute for some petroleum products. The bio-based cyclic carbonates are coupled of CO with vegetable oil-based epoxides, then reacted with amines leading to nipu(Scheme1). Compared to traditional methods of producing polyurethane, this method is safer and greener as it avoids the use of toxic materials such as isocyanates and it’s reaction conditions more responsive. At the same time, nipu shows enhanced thermal stability because it doesn’t have thermally labile biuret and allophanate groups incorporated in the PU backbone. In this work, we prepared nipu with different vegetable oils and diamines as monomers, and it reached a breaking point at stress of 5.2 MPa and strain of 261%.

关键词： nipu CO2 vegetable oils bio-based

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Chinese Journal of Polymer Science 2023年第7期41卷 1069-1077页

作者： Xiao-Jing Li Ying-Feng Wen Yong Wang Xing-Ping Zhou Xiao-Lin Xie Key Laboratory for Material Chemistry of Energy Conversion and Storage Ministry of EducationSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan430074China

Poly(propylene carbonate) (PPC) is gaining significant momentum as a biodegradable polymer using CO_(2) as an abundant, low-cost and renewable feedstock. Yet, PPC suffers from unsatisfactory thermal and mechanical properties, and its blends with other synthetic polymers as the second component typically exhibit poor compatibility. Herein, novel furan-based non-isocyanate polyurethanes (nipus) with high molecular weights and narrow distributions have been synthesized starting from 5-hydroxymethylfurfural (HMF) via a four-step procedure including reduction, glycidylation, carbonation of CO_(2) and step-growth polymerization with diamines. Owing to the structural similarity and intermolecular hydrogen bonding interactions, furan-based nipus display good compatibility with PPC. A sea-island morphology can be observed in SEM images of PPC/nipu blends, where the nipu phases are randomly dispersed in the PPC matrix. Moreover, the blends exhibit only one Tg (higher than both that of PPC and the corresponding nipu) on the DSC curves, which first increase and then decrease when increasing the content of nipus from 0 wt% to 15 wt%. Notably, the physical crosslinking formed by hydrogen bonding interactions, coupled with the rigidity of furan rings, confer simultaneous improvements of elongation at the break and tensile strength, affording high-performance CO_(2)-based biodegradable polymeric materials with low carbon footprint, good sustainability, and ideal biocompatibility.

关键词： PPC CO_(2) nipu HMF Blends

Glucose-Biobased Non-Isocyanate Polyurethane Rigid Foams

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Journal of Renewable Materials 2019年第3期7卷 301-312页

作者： Xuedong Xi A.Pizzi C.Gerardin Guanben Du LERMAB-ENSTIB University of LorraineEpinalFrance Southwest Forestry University KunmingYunnanChina LERMAB Faculty of SciencesUniversity of LorraineNancyFrance

Glucose-based non-isocyanate polyurethanes(nipu)were prepared by reaction of glucose with dimethyl carbonate and hexamethylene *** were used to prepare partially biobased polyurethane foams by reaction with NaHCO3 as a blowing agent and addition of a silane coupling agent having different functions such as coreactant and adjuvant to obtain more uniform and smaller *** foams were foamed and hardened by applying *** foams presented very limited fire resistance indicating that as for synthetic polyurethane foams the eventual use of a fire retardant appears to be *** 2 hours water absorption was used to indicate if close cells or open cells *** characteristic is their stress strain *** compression does indeed flatten the cell walls nonetheless the cellular structure is maintained and the cell walls have not been *** indicates a certain level of elasticity in the cell walls of formulations containing *** effect the macro-appearance of this foams,confirms this explanation as the foam is densified and holds together.

关键词： Polyurethane biofoams non-isocyanate polyurethanes nipu biofoams glucose

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非异氰酸酯聚氨酯材料的制备及应用

非异氰酸酯聚氨酯材料的制备及应用

作者：杨先瑞沈阳工业大学

学位级别：硕士

聚氨酯(PU)是主链上含有氨基甲酸酯结构单元的一类聚合物,由于其强极性的氨基甲酸酯基团的存在,PU具有良好的耐油性、韧性、耐老化性、耐磨性等特点,可广泛应用于建筑、机械、医药等行业。但是在制备PU的过程中需要使用异氰酸酯单体,由... 详细信息

聚氨酯(PU)是主链上含有氨基甲酸酯结构单元的一类聚合物,由于其强极性的氨基甲酸酯基团的存在,PU具有良好的耐油性、韧性、耐老化性、耐磨性等特点,可广泛应用于建筑、机械、医药等行业。但是在制备PU的过程中需要使用异氰酸酯单体,由于该种单体化学性质活泼、耐水性差、毒性较大,使得PU在生产、单体储运过程中存在一定的安全风险,因此开发非异氰酸酯聚氨酯(nipu)成为新材料领域的研究热点。相对于传统的PU,nipu在制备过程中不使用存在安全风险的异氰酸酯,而且nipu与传统PU在分子主链上都有氨基甲酸酯基团,具有类似的理化性质。同时,nipu分子链的每一个氨基甲酸酯基团都带有一个与其β位碳原子相连的羟基,能与氨基甲酸酯基团中的羰基氧原子形成分子内氢键,生成一个稳定的六元环结构,这就使得nipu比传统PU具有更加优良的耐化学性及抗渗透性等优点。因此,越来越多的国家开始重视nipu的开发,相关理论和应用研究也相应的得到了长足的发展。本论文以多元环状碳酸酯和二元胺作为单体,通过共聚制备出nipu材料。在此基础上,将nipu与竹纤维(BF)复合,制备出nipu复合材料。主要研究内容包括。多元环状碳酸酯的制备。以基于生物质的环氧大豆油(ESBO)为原料,将其与CO反应,制备环状碳酸酯大豆油(CSBO),研究反应温度、反应压力、反应时间和催化剂用量等反应条件对ESBO转化率的影响。并通过傅里叶红外(FT-IR)和核磁氢谱(H-NMR)等表征手段,研究CSBO的结构。研究表明,当反应温度为120℃,催化剂加量为2 wt.%,CO压强为2 Mpa,反应时间为20 h时,ESBO的转化率可达98.5%。对CSBO的红外结构分析表明,产物中在1793 cm处出现了CSBO环状碳酸酯中羰基基团的红外振动,环氧官能团在823 cm和843 cm的红外振动基本消失。产物的核磁分析表明,产物中在4.40～4.94 ppm处出现了CSBO环状碳酸酯基团中氢的化学位移,反应物在2.83～3.25 ppm处的ESBO环氧基团的氢化学位移基本消失。这些研究结果说明成功制备出了CSBO。nipu的制备。将制备的CSBO与二胺通过共聚反应制备nipu。研究了CSBO与二胺的比例、固化温度、固化时间和二胺的种类等对制备的nipu性能的影响。通过FT-IR、热重分析(TG)、差热扫描量热分析(DSC)和力学性能分析等表征手段,对nipu的结构与性能之间的关系进行了研究。研究表明,在反应条件为:CSBO/伯胺官能团摩尔比为1:1.1,固化温度为80℃,固化时间为9 h时,制备得到的nipu的力学性能最好。对不同二胺制备的nipu的结构性能对比分析表明,使用乙二胺(EDA)制备得到的nipu的力学性能最优,拉伸强度7.0 Mpa,杨氏模量达到5.5 Mpa。nipu复合材料的制备。在制备nipu的过程中,将BF与CSBO和己二胺(HMDA)进行共混,在共聚的过程中制备得到nipu复合材料。通过FT-IR、TG、DSC和力学性能测试等表征手段,研究了BF对于nipu复合材料结构和力学性能的影响。FT-TR研究结果表明,BF与nipu产生了强的相互作用。力学性能研究结果表明,BF的添加能有效改善nipu复合材料的力学性能,添加40%BF的复合材料,其拉伸强度相比相应的nipu材料提高了5.3倍,杨氏模量提高了910.9倍。

关键词： ESBO 二元胺 nipu BF 复合材料

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非异氰酸酯聚氨酯的制备与固化动力学

非异氰酸酯聚氨酯的制备与固化动力学

作者：赵福光青岛科技大学

学位级别：硕士

传统聚氨酯因具有优良的性能而受到广泛的应用，但异氰酸酯作为合成传统PU材料的原料之一，在制备以及使用的过程中都存在着许多问题。本论文以不同种类的环氧树脂为基础，与CO2反应合成了不同类型的环碳酸酯（CC），再让其与多元胺反... 详细信息

传统聚氨酯因具有优良的性能而受到广泛的应用，但异氰酸酯作为合成传统PU材料的原料之一，在制备以及使用的过程中都存在着许多问题。本论文以不同种类的环氧树脂为基础，与CO2反应合成了不同类型的环碳酸酯（CC），再让其与多元胺反应合成了非异氰酸酯聚氨酯（nipu）。研究了nipu的固化动力学，并通过改变制备nipu的原料配比合成了力学性能以及热力学性能都相对优异的材料。主要研究内容如下：1）以不同类型的多官能度环氧树脂以及无毒且资源丰富的CO2为原料合成了末端含有五元环碳酸酯基团的多元环碳酸酯（CC）。并且分别又以此单体为原料，与多元胺反应合成了nipu。同时采用红外光谱（FI-IR）以及核磁共振氢谱（1H-NMR）表征了合成产物的化学结构。2）利用不同质量比的PEG400二缩水甘油醚（PEG400DGE）与双酚F型环氧树脂NPEF-170制备了混合环碳酸酯，并且研究了温度、压力、反应时间以及催化剂的用量与种类对环氧树脂转化率的影响。研究表明，当使用质量分数为0.5%的四丁基溴化铵（TBAB），温度为120℃、二氧化碳压力为1.8MPa，反应7h后可以达81.5%的转化率。3）利用非等温DSC的方法，研究了在不同的升温速率下，混合环碳酸酯与聚醚胺T403的固化反应动力学，并优化了固化工艺。研究结果表明，该体系的凝胶温度为373.25K，固化温度为448.70K，后固化温度为506.80K，固化时间为15min。4）在相同的条件下，研究了不同配比的环碳酸酯对所制备的nipu材料的力学性能以及热力学性能的影响。研究表明，当PEG型环碳酸酯（PEG-CC）与NPEF型环碳酸酯（NPEG-CC）的质量比为3:7时所制备的nipu材料的力学性能与热力学性能达到最佳状态。最大拉伸强度为7.58MPa，扯断伸长率为347%，定伸率强度为3.03%，玻璃化转变温度（Tg）为11.16℃。

关键词：环氧树脂 CO2环碳酸酯 nipu 固化动力学

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后金融危机下我国聚氨酯弹性体发展之路探讨

化学推进剂与高分子材料 2011年第1期9卷 10-17页

作者：黄茂松贾润萍上海应用技术学院材料科学与工程学院上海200235 上海PU产业发展促进中心上海200235

评述了我国聚氨酯(PU)弹性体的重要地位,重点论述了后金融危机下我国汽车工业、高铁和城市轨道交通、新能源、海洋工程和高端装备制造业是PU弹性体未来发展的新动力之源。指出TPU(热塑型PU)切片、TPU薄膜、TPU医疗制品、TPU合金、TPU/T... 详细信息

评述了我国聚氨酯(PU)弹性体的重要地位,重点论述了后金融危机下我国汽车工业、高铁和城市轨道交通、新能源、海洋工程和高端装备制造业是PU弹性体未来发展的新动力之源。指出TPU(热塑型PU)切片、TPU薄膜、TPU医疗制品、TPU合金、TPU/TPV(热塑性硫化橡胶)是TPU弹性体未来发展方向,PU轮胎是CPU(浇注型PU)弹性体未来重要发展方向,PU皮革和PU鞋材树脂制品是我国微孔弹性体主要产品形式和出口产品,PU复合材料和PU功能材料是值得关注的PU弹性体新材料。提出开发生物降解PU弹性体的主要技术途径和应用前景。PU风机叶片、PU枕木、碳纳米管/FPU(含氟PU)、HPPO-PO(双氧水丙烯直接氧化法生产环氧丙烷)、ADI(脂肪族和脂环族二异氰酸酯)和nipu(非异氰酸酯聚氨酯)是具有前瞻性的低碳开发项目。

关键词： TPU CPU 生物降解PU nipu

第四十九讲后金融危机下我国聚氨酯弹性体发展之路探讨

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环球聚氨酯 2011年第4期 74-80页

作者：黄茂松贾润萍上海应用技术学院材料科学与工程学院上海PU产业发展促进中心

本文评述了我国聚氨酯(PU)弹性体的重要地位,重点论述了后金融危机下我国汽车工业、高铁和城市轨道交通、新能源、海洋工程和高端装备制造业是PU弹性体未来发展的新的动力之源。指出TPU(热塑型PU)切片、TPU薄膜、TPU医疗制品、TPU合金、... 详细信息

本文评述了我国聚氨酯(PU)弹性体的重要地位,重点论述了后金融危机下我国汽车工业、高铁和城市轨道交通、新能源、海洋工程和高端装备制造业是PU弹性体未来发展的新的动力之源。指出TPU(热塑型PU)切片、TPU薄膜、TPU医疗制品、TPU合金、TPU/TPV(热塑性硫化橡胶)是TPU弹性体未来发展方向。PU轮胎是CPU(浇注型PU)弹性体未来重要发展方向。PU皮革和PU鞋材树脂制品是我国微孔弹性体主要产品形式和出口产品。PU复合材料和PU功能材料是值得关注的PU弹性体新材料。提出开发生物降解PU弹性体的主要技术途径和应用前景。PU风机叶片、PU枕木、碳纳米管/FPU(含氟PU)、HPPO-PO(双氧水丙烯直接氧化法)、ADI(脂肪族和脂环族二异氰酸酯)和nipu(非异氰酸酯聚氨酯)是具有前瞻性的低碳开发项目。

关键词： TPU CPU轮胎生物降解PU nipu