聚甲基丙烯酰亚胺泡沫塑料研究进展

综述了聚甲基丙烯酰亚胺(PMI)泡沫塑料的制备方法、性能、国内外研究概况和应用情况,并指出了今后PMI泡沫塑料研究的方向。     

聚甲基丙烯酰亚胺硬质泡沫塑料

聚甲基丙烯酰亚胺（PMI）硬质泡沫塑料很长时间以来就为大家所知,它是一种交联、闭孔的泡沫塑料,而且由于其优异的机械性能和低的重量而有广泛的应用,特别是生产层状材料、层压材料、复合材料或泡沫复合体,是制造高性能夹层结构的理想芯层材料。综述了聚甲基丙烯酰亚胺（PMI）硬质泡沫塑料的性能特点、制备以及它的一些应用情况。PMI硬质泡沫塑料代表着新型的高性能泡沫塑料的研究方向。     

聚甲基丙烯酰亚胺泡沫塑料的制备及研究现状

以丙烯腈(AN)、-甲基丙烯酸(MAA)为主要单体原料,以丙烯酰胺(AM)为第三共聚单体,加入引发剂、发泡剂等自由基本体聚合制得AN-MAA-AM共聚物,然后在高温下将AN-MAA-AM共聚物进行高温发泡得到聚甲基丙烯酰亚胺(PMI)泡沫塑料。详细介绍了PMI泡沫塑料的制备和研究现状,并对PMI泡沫塑料的研究方向进行了展望。     

聚甲基丙烯酰亚胺泡沫材料生产研究进展

综述了聚甲基丙烯酰亚胺(PMI)泡沫材料的性能、制备工艺、国内外生产研究和应用情况,并指出了今后PMI泡沫塑料研究的方向。     

聚甲基丙烯酰亚胺泡沫

湖南塑料研究所在国内率先研制出聚甲基丙烯酰亚胺（PMI）泡沫。PMI泡沫是一种交联的闭孔结构泡沫，具有良好的力学性能、热变形温度（180～240℃）和化学稳定性。密度可控制在50-150kg／m^3，在相同密度的泡沫中PMI泡沫的强度和刚度是所有泡沫中最高的。PMI泡沫作为夹芯材料时，可采用Scrimp法、纤维缠绕法、加压铸造法等方法制造复合材料。PMI泡沫作为复合材料的夹芯，在复合材料的质量设计及优化和制造方面具有明显的优势。     

聚甲基丙烯酰亚胺泡沫材料的研究进展

综述了国内外对于聚甲基丙烯酰亚胺(PMI)泡沫材料的研究成果与进展.分别从材料的合成和改性两个方面对PMI的研究现状进行了说明,并比较了各种合成方法的优缺点,最后展望了未来我国PMI产业的发展趋势.     

低成本制备聚甲基丙烯酰亚胺泡沫的研究进展

从配方和成型工艺两方面综述了聚甲基丙烯酰亚胺泡沫低成本制备技术的研究进展,并指出了该领域未来的研究方向.     

聚甲基丙烯酰亚胺泡沫的制备及其压缩性能

聚甲基丙烯酰亚胺(PMI)泡沫通过两步制得:(1)本体聚合得到可发性的甲基丙烯酸/丙烯腈共聚物板;(2)190℃发泡1 h制得PMI泡沫.采用电子万能试验机、数码照相机和扫描电子显微镜对压缩及拉伸性能进行了分析.表明热处理之后泡沫压缩强度有大幅提高;拉伸强度提高幅度较小,但断裂伸长率明显下降;压缩破坏源于泡孔结构的皱弯变形,并形成屈服层,呈现出层层扩散式破坏特征.     

聚甲基丙烯酰亚胺(PMI)泡沫的进展

聚甲基丙烯酰亚胺(Polymethacrylimide,PMI)泡沫是当今夹层结构复合材料最主要的芯材,具有密度低、力学性能和耐热性能突出、易于机加工、与热固性树脂黏结良好、适应于热压罐固化工艺等突出优点,已经在航空航天、交通运输、风电叶片、医疗器械、电子通讯等领域获得较广泛应用.本文对PMI泡沫的发展历史、制备技术、...     

Research on rapid preparation and performance of polymethacrylimide foams

A high‐performance polymethacrylimide (PMI) foam was prepared from the reactive monomers of acrylonitrile (AN) and methacrylic acid (MAA) via ultrasonic combined with thermal initiation radical bulk copolymerization and free heat foaming. The reaction progress of cyano and carboxyl groups were tracked by Fourier transform infrared (FTIR) spectroscopy and X‐ray Photoelectron Spectroscopy, and the results indicated that the imide groups were formed and cyano groups gradually decreased during foaming and thermal treatment. The cell morphologies of the PMI foams were characterized by scanning electron microscopy, and the results showed the PMI foams were consisted of the honeycomb structure. The thermostability of the prepared PMI foam was evaluated by thermogravimetric analysis (TGA), and the results revealed that the PMI foam possessed excellent thermal stability and char forming capability. The mechanical properties of PMI foams were measured by tensile, flexural, and compressive strength, and the responding values for the PMI foams with the density of 32.30 kg m^?3 were 0.71, 0.86, and 1.49 MPa, respectively, which demonstrated the obtained PMI foams presented superior mechanical properties. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44959.     

Preparation and properties of polymide foams

Catalysts for the raction of aromatic isocyanates with aromatic anhydrides to form imides were investigated using a model reaction. Alkali metal acetylacetone chelate compounds exhibited good catalytic efficiency and selectivity in dimethyl sulfoxide (DMSO). These catalysts were used for the preparation of polymide foams. The resulting foams exhibited excellent fire resistance and thermal stability. © 1994 John Wiley & Sons, Inc.     

超软质聚氨酯泡沫的制备

概述了超软质聚氯酯泡沫的几种主要制备方法。     

海藻酸-壳聚糖复合海绵的制备与性能研究

为了制备出结构相对均匀的海藻酸-壳聚糖(ALG-CS)复合海绵(AC),文中采用海藻酸(ALG)发泡液与壳聚糖(CS)发泡液复合的方法以避免复合过程中聚电解质复合物团聚现象。分别对AC的表观结构、溶胀动力学以及黏度、吸液率、保液率和力学性能进行了测定。实验结果表明:ALG/CS发泡液体积比(10∶1)—(2∶1),复合发泡液黏度变化不大,可获得孔结构相对均匀的复合海绵;复合海绵的溶胀过程符合Schott二级溶胀动力学模型;随壳聚糖含量增加,复合海绵吸液率下降,拉伸强度提高,同时可提高复合海绵抗溶剂性能;AC6复合海绵溶胀速率较低,保液率高,这可能与其刚性较强有关。     

Polyvinylcarbazole foams. I. Preparation

The polymerization of vinylcarbazole in aqueous dispersion by azobisisobutyronitrile can yield–depending on the protective colloid used–polyvinylcarbazole beads or granules. These require impregnation by a polymer solvent and preferably also by azobisisobutyronitrile before they can be molded to panels or simple shapes.     

粉末法制备聚酰亚胺泡沫塑料

以芳香二酐和二胺为单体,甲醇/四氢呋喃为溶剂,通过酯化法合成聚酯铵盐前驱体粉末、粉末法制备泡孔均匀的聚酰亚胺泡沫塑料.采用扫描电子显微镜照片、傅里叶变换红外光谱和热重分析表征泡沫材料结构及耐热性能,研究了初始加热温度、粉末粒径对泡沫密度的影响.结果表明:初始加热温度越高,泡沫密度越小.粉末粒径对泡沫密度影响较小.     

Preparation of carbon foams with supercritical toluene

Carbon foams with pore sizes of 10–50 μm were prepared with mesophase pitch and toluene as the carbonaceous precursor and supercritical agent, respectively. Results revealed that the light pitch components and dissolved toluene in pitch significantly affected the pore structures of resultant carbon foams. The amount of toluene dissolved in molten pitch is greatly dependent on the foaming conditions, such as the ratio of toluene to pitch, foaming temperature, foaming pressure and saturation time. Carbon foams with hierarchical porous structures are obtained by controlling the amount of light pitch components.     

Preparation of foams from vegetable oil derivatives

Dimer acid was hydroxyethylated at 110–240C in the presence of alkaline catalysts. Products having ethylene oxide: dimer acid mole ratios of 0.8 to 1.4 were transformed into flexible urethane foams of density 2.0 to 4.4 lb/ft³. Hydrogenated “aldehyde oil” gave a rigid foam which had a density of 1.2 lb/ft³. A laboratory of the Northern Utilization Research and Development Division, Agricultural Research Service, USDA.     

Preparation and characterization of polystyrene foams from limonene solutions

The foaming process has been traditionally performed at high temperature because the CO₂ and the polymer should behave as a homogeneous solution. The addition of a solvent could avoid the high working temperature while the homogeneity is ensured. Among the terpene oils, limonene outlines as a good candidate to carry out the dissolution of polystyrene because it respects the green chemistry principle, it is highly soluble in CO₂ and very compatible with the polymer.The sorption of CO₂ is the first step of the foaming process. The presence of the terpene oil enhances the solubility of the gas which is solubilized in the Polystyrene as well as in the limonene. During the foaming process, many parameters can be tuned to customize the foams. In this work, a fractional factorial design of experiment was proposed to determine the effect of pressure, temperature, concentration of the solution, contact time and vent time over the diameter of cells, its standard deviation and the cells density. The proposed foaming process can be simply performed at mild pressure and temperature thanks to the presence of the solvent. The results showed that the most suitable conditions to foam polystyrene from limonene solutions are 90 bar, 30 °C, 0.1 gPS/ml Lim, 240 min contacting and 30 min venting. Finally, the samples were characterized to determine the amount of residual solvent, their glass transition and degradation temperature checking that the foams presented around 5% of solvent traces but did not show any evidence of degradation.