基于醇胺固定-释放二氧化碳原理的聚氨酯泡沫绿色制备

通过二乙醇胺(DEA)和二氧化碳反应制得一种氨基甲酸铵化合物(DEAC)。DEAC初始分解温度约为54℃,二氧化碳含量14.6%。将不同份数的DEAC作为反应型发泡剂添加到硬质聚氨酯发泡体系中制备泡沫材料,得到密度为90~150 kg·m~(-3),压缩强度为0.02~1.65 MPa性能良好的泡沫材料。DEA在火力发电厂作为二氧化碳吸收剂以减少二氧化碳排放。因此,DEAC可以来源于火力发电厂的副产物,成本低廉。本研究为硬质聚氨酯泡沫的制备提供了一种新型的绿色、环保、经济的方法。     

聚氨酯的应用和开发研究

1聚氨酯的应用 聚氨酯（PU）树脂是由异氰酸酯与多元醇反应制成的一种具有氨基甲酸酯链段重复结构单元的聚合物。聚氨酯制品可分为泡沫制品和非泡沫制品两大类，而泡沫制品有软质、硬质、半硬质之分，非泡沫制品则包括涂料、胶粘剂、弹性体和弹性纤维（氨纶）等。聚氨酯材料性能优异，用途广泛，其各种不同的制品可以用于众多领域。     

专利文摘

一种吸波聚氨酯角锥/硬质泡沫复合材料及制备方法(CN112126115A)航天特种材料及工艺技术研究所给出一种吸波聚氨酯角锥/硬质泡沫复合材料及制备方法,该复合材料由吸波聚氨酯海绵角锥和硬质泡沫组成。将吸收剂浆料通过浸渍方式沉积于聚氨酯海绵角锥孔壁和骨架上,形成吸波聚氨酯海绵角锥,再进行硬质泡沫发泡,填充于聚氨酯角锥中间区域和海绵泡孔内获得吸波聚氨酯角锥/硬质泡沫复合材料。     

蒸馏水含量对三明治结构硬质聚氨酯泡沫性能的影响

采用异氰酸酯、聚酯多元醇、发泡剂（水）等原料通过一体发泡成型技术制备出一种新型的三明治泡沫夹心复合材料。利用热重分析、扫描电子显微镜等对不同水含量（质量分数分别为0、0.5 %和1.0 %）的硬质聚氨酯泡沫材料的泡孔直径、密度、热导率、压缩性能、三点弯曲和热力学性能等做了研究,进而确定提高硬质聚氨酯性能的最佳工艺。结果表明,随着水含量的增加,硬质聚氨酯泡沫材料泡孔直径增大,密度变小,热导率降低,保温性能提高,而压缩性能和三点弯曲却呈下降趋势;综合考虑硬质聚氨酯泡沫材料泡孔结构和良好的保温隔热及弯曲等力学性能,其最佳含水量为0.5 %。     

无卤阻燃型硬质聚氨酯泡沫塑料的研究进展

综述了近年来有关无卤阻燃型聚氨酯硬质泡沫的制备方法,包括含磷、含氮、无机和复合阻燃型泡沫。介绍了国内外阻燃型聚氨酯硬质泡沫材料的最新情况,讨论了阻燃剂的阻燃机理,并展望了阻燃型聚氨酯硬质泡沫材料的发展趋势。     

聚氨酯／蒙脱土复合阻燃硬质泡沫材料的研究

采用原位聚合法制备了蒙脱土阻燃硬质聚氨酯泡沫材料,并用多种添加型阻燃剂制备了阻燃聚氨酯硬质泡沫,同时尝试有机改性蒙脱土与添加型阻燃剂并用对聚氨酯硬质泡沫进行阻燃。用锥形量热仪测试了阻燃聚氨酯泡沫材料的燃烧性能,结果发现,材料的热释放速率、质量损失速率与纯聚氨酯硬质泡沫相比均显著降低,峰值热释放速率最多降低到纯硬质泡沫的55％,表明制备的泡沫材料具有较好的阻燃性。用X-射线衍射和扫描电镜分析了蒙脱土及有机改性蒙脱土的微观结构。通过分析材料的燃烧性能和燃烧残余物,探讨了其可能的阻燃机理。     

反应与添加型硬质聚氨酯泡沫阻燃剂研究进展

硬质聚氨酯泡沫是一种保温隔热性能良好的泡沫材料,被广泛应用于各个领域。研究其阻燃性能对其广泛应用有重要意义。概述了阻燃剂的阻燃机理,综述了反应型与添加型硬质聚氨酯泡沫阻燃剂的研究进展,包括磷系、氮系、复合和膨胀型等阻燃剂的研究,最后对阻燃型硬质聚氨酯泡沫的市场前景进行了展望。     

物理发泡水稻秸秆基聚氨酯泡沫研究

将水稻秸秆粉碎为粒径250~590 μm的粉末，利用成熟的催化常压加热液化技术将水稻秸秆粉末液化制得液化物，以其为原料，五甲基二乙烯三胺（PC5）和N，N-二甲基环己胺（PC8）为复合催化剂，正戊烷为发泡剂，与多苯基甲烷多异氰酸酯（PAPI）反应通过物理发泡法制备硬质聚氨酯泡沫（PURF）。另外采用全水发泡法制备了聚氨酯泡沫作为对比。对物理发泡制备PURF的条件进行了优化，较优的制备条件为催化剂中PC5和PC8的质量比4:5，泡沫稳定剂硅油B8462用量（以液化物质量计，下同）4%，发泡剂用量15%，该条件下制备的PURF的拉伸强度为347 kPa，压缩强度为181 kPa。采用傅里叶变换红外光谱（FT-IR）和扫描电镜（SEM）对比了物理发泡和全水发泡制得的泡沫，结果显示，通过物理发泡制得的水稻秸秆基聚氨酯泡沫相比于全水发泡聚氨酯泡沫，体系中异氰酸根浓度低，泡沫泡孔开孔率低，制得的泡沫力学性能略优。     

端羟基液体橡胶改性RPUF的结构与力学性能

制备了3种端羟基液体橡胶改性硬质聚氨酯泡沫塑料(RPUF)。研究了所制备材料的形态结构,以及泡沫材料的冲击韧性、屈服强度模量、缓冲吸能特性和阻尼性能与材料密度、液体橡胶的含量和液体橡胶的种类之间的关系。结果表明,粘度较低的端羟基聚丁二烯改性的硬质聚氨酯泡沫具有更好的冲击韧性;粘度较高、含极性氰基端羟基聚丁二烯丙烯腈改性的硬质聚氨酯泡沫塑料具有较低的屈服强度、模量和缓冲能量吸收值,具有较高的力学损耗。为高阻尼硬质聚氨酯泡沫塑料的制备奠定了基础。     

腰果壳油生物基多元醇的合成及硬泡领域的应用

采用腰果壳油、甲醛及二乙醇胺发生曼尼希反应(Mannich)合成了腰果壳油生物基多元醇,并以此多元醇制备了低吸水率硬质聚氨酯泡沫。合成实验结果表明:腰果壳油/甲醛/二乙醇胺的最佳投料摩尔比1∶1.2∶1,最佳反应温度为80℃,反应时间为1.5 h。发泡结果表明:腰果壳油生物基多元醇制备的硬质聚氨酯泡沫具有良好的低吸水率性能,且在使用份数为40~45份时吸水率最低达到1.3%。腰果壳油生物基多元醇在低吸水率硬质聚氨酯泡沫领域具有一定的应用前景。     

AN EXPERIMENTAL INVESTIGATION INTO THE FOAMING TENDENCY OF DIETHANOLAMINE GAS SWEETENING SOLUTIONS

The foaming tendency of a 30 weight % solution of diethanolamine (DEA) in distilled water was measured over a temperature range of 20-85°C and a pressure range of 1-3 MPa in the presense of a number of contaminants including carboxylic acids, oils, 1-4 bis (2-hydroxyethyl) piperazine (HEP), methanol, iron sulphide, silicone antifoam, etc. The measurements were conducted using a Jerguson high pressure sight glass contained in an air bath. Foaming was measured at gas rates up to 7.5 standard m³/d using air, nitrogen, carbon dioxide, and ethane. One notable observation was that the addition of most of the contaminants commonly identified as foam promoters did not create a foaming system with a clean 30% DEA solution. In fact, the only solutes that produced significant foaming were the carboxylic acids as noted previously in the literature by Pauley et al. (1989). The addition of contaminants to a foaming system did increase foam heights and stability substantially and results are presented for methanol and HEP addition to a foaming system of DEA-carboxylic acid. The effects of temperature, pressure, and gas flow rates on foam heights and foam break times were measured for a number of systems. Foaming was increased by a higher temperature and by higher pressure and was much more pronounced when carbon dioxide or ethane gases were used     

CO2-原油体系发泡特性实验研究

为研究CO₂驱油田分离器内泡沫层产生及消除机理,设计了一套高压溶气原油泡沫测试系统,采用降压法研究了CO₂-原油体系的发泡特性。利用高速摄像机对泡沫产生至衰变的演变过程进行了记录,总结分析了不同降压阶段的气泡行为,研究了降压速率和搅拌速率对原油发泡特性的影响规律。研究发现,随压力降低,稳定存在气泡的直径增大,气泡位置上移,发泡行为更加剧烈;降压速率增加对降压阶段的发泡行为无明显影响,但会加剧稳定工作压力下的发泡行为;在转速小于等于120 r/min的条件下,搅拌速率增加会加剧降压阶段的发泡行为,但会加速稳定工作压力下的泡沫衰变。     

一步法制备含氨基化合物的非对称CO2分离膜

采用一步相分离法,制备以聚醚砜（PES）为主体材料,二乙醇胺（DEA）为添加剂和氨基载体的膜,用于CO₂分离。考察了PES浓度、DEA浓度、膜厚度对CO₂/N₂分离性能的影响,同时考察了膜性能的长时间稳定性。当涂膜液中DEA/PES的质量比为12/26、刮刀与无纺布的距离为300 μm、进料气压力为0.11 MPa（表压）时,膜的CO₂渗透速率可达274 GPU,CO₂/N₂分离因子可达50。测试温度低于40℃时,DEA/PES膜的CO₂渗透速率和CO₂/N₂分离因子保持稳定。另外,对CO₂/N₂分离性能较好的DEA/PES膜（质量比为12/27）进行CO₂/CH₄分离性能测试,在1 MPa（表压）下性能优于商品膜。上述结果表明,本文研制的DEA/PES膜制备步骤简单,易于规模化制备,性能较优,在CO₂分离领域具有良好的应用前景。     

SOLUBILITY OF NITROUS OXIDE IN AQUEOUS SOLUTIONS OF METHYLDIETHANOLAMINE, DIETHANOLAMINE AND MIXTURES OF METHYLDIETHANOLAMINE AND DIETHANOLAMINE

The solubility of nitrous oxide (N₂O) in aqueous solutions of 0-50 mass % methyldiethanolamine (MDEA), 0-30 mass % diethanolamine (DEA), and 50 mass % total amine with DEA/MDEA weight ratios of 0.04413-0.5883 was measured over the temperature range 293-353 K and at N₂O partial pressures near atmospheric. The solubility data from this work were found to be in fair agreement with the literature where data were available. The N₂O solubility data for the aqueous MDEA and aqueous DEA solutions were fitted using the extended scaled-particle model proposed by Li and Mather (1994) (which was based on the work of Hu et al. (1985)). The parameter estimates obtained from these fits were then used to predict the N₂O solubility in the aqueous DEA + MDEA solutions. The model predictions were found to agree with the experimental data with an average deviation of 3.4%     

In-situ Polymerization-modification Process and Foaming of Poly（ethylene terephthalate）

Most of traditional linear poly（ethylene terephthalate）（PET） resins of relatively low molecular mass and narrow molecular mass distribution have low melt strength at foaming temperatures, which are not enough to support and keep cells. An in-situ polymerization-modification process with esterification and polycondensation stages was performed in a 2 L batch stirred reactor using pyromellitic dianhydride（PMDA） or pentaerythritol（PENTA） as modifying monomers to obtain PETs with high melt strength. The influence of amounts of modifying monomers on the properties of modified PET was investigated. It was found that the selected modifying monomers could effectively introduce branched structures into the modified PETs and improve their melt strength. With increasing the amount of the modifying monomer, the melt strength of the modified PET increased. But when the amount of PENTA reached 0.35% or PMDA reached 0.9%, crosslinking phenomenon was observed in the modified PET. Supercritical carbon dioxide（ScCO2） was employed as physical foaming agent to evaluate the foaming ability of modified PETs. The modified PETs had good foaming properties at 14 MPa of CO2 pressure with foaming temperature ranging from 265 °C to 280 °C. SEM micrographs demonstrated that both modified PET foams had homogeneous cellular structures, with cell diameter ranging from 35 μm to 49 μm for PENTA modified PETs and 38 μm to 57 μm for PMDA modified ones. Correspondingly, the cell density had a range of 3.5×107cells·cm 3to 7×106 cells·cm 3for the former and 2.8×107cells·cm 3to 5.8×106cells·cm 3for the latter.     

Synthesis, characterization and catalytic properties of SAPO-34 synthesized using diethylamine as a template

SAPO-34 molecular sieve was successfully synthesized using diethylamine (DEA) as a template. The influence of template concentration and silica concentration on the synthesis were investigated. Pure SAPO-34 could be obtained when n(DEA)/n(Al₂O₃)  1.5 and n(SiO₂)/n(Al₂O₃) > 0.1 in the synthesis gel. Further increase of DEA concentration in the starting gel [n(DEA)/n(Al₂O₃) > 3] has a negative effect on both crystallinity and crystal yield. The products were characterized by XRD, XRF, SEM, NMR, FT-IR, TG-DTA and nitrogen adsorption techniques. It was found that SAPO-34 synthesized with DEA as a template has the characteristic of high silicon incorporation and exhibits good thermal and hydrothermal stability. The catalytic performance of SAPO-34 was tested by methanol-to-olefin (MTO) reaction and high olefins (C₂H₄ + C₃H₆) selectivity was obtained.     

利用13C NMR技术探究叔胺溶液中HCO3-的生成

利用¹³C NMR技术对CO₂捕获叔胺溶剂进行了碳元素的定量研究,主要考察了对胺溶剂解吸热影响较大的HCO₃^-的生成规律。重点对叔胺分子结构中羟基官能团(-OH)、羟烷基数目、烷基支链及氮原子(N)所连接烷基链大小对胺溶剂生成HCO₃^-的影响。在20℃条件下分别对1 mol·L^-1具有不同CO₂负载的1-二甲基氨基-2-丙醇(1DMA2P)、N-甲基二乙醇胺(MDEA)、3-二甲氨基-1-丙醇(3DMA1P)、二乙氨基-2-丙醇(1DEA2P)、N,N-二乙基乙醇胺(DEEA)、N,N-二甲基乙醇胺(DMMEA)及三乙醇胺(TEA)溶液进行了¹³C NMR测试研究。实验结果显示:在相同浓度的叔胺水溶液中,同一CO₂负载下的叔胺-CO₂-水体系中HCO₃^-的含量顺序为:DMMEA > MDEA>3DMA1P > 1DMA2P > TEA > DEEA > 1DEA2P。通过对各叔胺分子结构中N原子的电子云密度大小及空间位阻效应分析,得出如下结论:3DMA1P分子中-OH官能团离N原子的距离大于其在DMMEA分子中的距离,导致其生成了较少的HCO₃^-;DMMEA分子中N原子上连接的烷基链小于DEEA分子中N原子上的烷基链,导致DMMEA溶液中生成了更多的HCO₃^-;MDEA分子中羟烷基数目少于TEA分子中的羟烷基数目,且MDEA比TEA多了一个甲基,导致MDEA溶液中含有更多的HCO₃^-;3DMA1P相比1DMA2P、DEEA相比1DEA2P分子中都少了一个甲基支链,导致3DMA1P溶液相比1DMA2P溶液、DEEA溶液相比1DEA2P溶液生成了更多的HCO₃^-。     

聚乙烯醇发泡材料研究进展

从化学发泡剂和物理发泡剂两个方面综述了聚乙烯醇(PVAL)发泡材料的发泡工艺,着重介绍了无机发泡剂和有机发泡剂两种化学发泡剂以及超临界CO₂物理发泡剂对PVAL发泡材料泡孔尺寸、孔径、力学性能等的影响,不同发泡剂具有不同的特点,绿色环保的超临界CO₂发泡剂将是今后研究的重点。此外,对PVAL发泡材料在生物医学领域、污水处理及包装领域的应用现状进行了介绍。     

Carbon foams prepared from coal tar pitch for building thermal insulation material with low cost

A new approach is provided to resolve the large-scale applications of coal tar pitch. Carbon foams with uniform pore size are prepared at the foaming pressure of normal pressure using coal tar pitch as raw materials. The physical and chemical performance of high softening point pitch(HSPP) can be regulated by vacuumizing owing to the cooperation of vacuumizing and polycondensation. Results indicate that the optimum softening point and weight ratio of quinoline insoluble are about 292℃ and 65.7%, respectively. And the optimum viscosity of HSPP during the foaming process is distributed in the range of 1000-10000 Pa·s. The resultant carbon foam exhibits excellent performance, such as uniform pore structure, high compressive strength(4.7 MPa), low thermal conductivity(0.07 W·m~(-1) ·K~(-1)), specially, it cannot be fired under the high temperature of 1200 ℃.Thus, this kind of carbon foam is a potential candidate for thermal insulation material applied in energy saving building.     

聚醚砜超临界CO2发泡行为研究

以超临界CO₂为发泡剂,采用间歇发泡法制备了聚醚砜（PES）泡沫。采用旋转流变仪和扫描电子显微镜分析表征了PES发泡的均相成核行为,继而分别以滑石粉和二氧化硅（SiO₂）作为异相成核剂,探究了PES发泡过程中的异相成核行为。结果表明,间歇发泡法制备PES泡沫的发泡区间为200~230 ℃;最佳浸泡压力为20 MPa;最佳浸泡时间为3 h;未改性PES的泡孔直径均可在10 μm以下,泡孔密度在10⁹~10¹⁰ 个/cm³之间,但泡孔壁较厚;SiO₂相对于Talc,表现出更显著的异相成核作用;在210 ℃、3 h、20 MPa的发泡条件下,添加0.9 %（质量分数,下同）的SiO₂,可得到泡孔直径为0.77 μm,泡孔密度为7.14×10¹¹ 个/cm³的PES微孔泡沫。