水对硬质聚氨酯泡沫塑料性能的影响研究

采用一步法合成了硬质聚氯酯泡沫塑料(PUF-R),考察了水的用量对PUF-R的表观芯密度、导热系数、拉伸强度、弯曲强度、压缩强度等性能影响,并利用扫描电子显微镜观察了泡孔形态.结果表明,随着水用量的增加,RPUF的密度、导热系数、拉伸强度、弯曲强度、压缩强度逐渐降低,储能模量随之下降,而泡孔直径则逐渐增大.     

辛基改性聚乙烯亚胺CO_2加合物的聚氨酯硬泡应用

分别以直链和支链辛基改性的聚乙烯亚胺的CO_2加合物为发泡剂,用蓖麻油多元醇Polycin T-400、聚合MDI等为原料制备了一系列硬质聚氨酯泡沫塑料。在用量相同的情况下,两种发泡剂与蓖麻油多元醇的相容性基本一样,都能形成半透明溶液;且发泡效率无差别,得到的泡沫密度和力学性能一致,说明侧链的支化结构对发泡剂的性能无显著影响。     

室温固化型MDI体系聚氨酯弹性体力学性能的研究

以不同结构多元醇和4,4′-二苯基甲烷二异氰酸酯(MDI-100)合成预聚体,再与不同扩链剂反应制备室温固化MDI型聚氨酯弹性体。讨论了多元醇种类、扩链剂种类、扩链系数、稀释剂用量、催化剂种类对聚氨酯弹性体力学性能的影响。结果表明,结构规整的多元醇制备的聚氨酯弹性体综合性能较好;二醇类扩链剂1,4-丁二醇(1,4-BDO)和对苯二酚二羟基乙基醚(HQEE)制备的弹性体性能较好,操作工艺可行;扩链系数以0.85~1.0为宜;适宜稀释剂质量分数为5%~10%;MDI室温固化体系的催化剂可选用HDcat。     

高性能浇注型聚氨酯弹性体的耐热性能

用不同结构的多元醇和二异氰酸酯合成了一系列浇注型聚氨酯弹性体(PU),研究了PU的物理机械性能、耐热性和动态力学性能.结果表明,当二异氰酸酯选为对苯二异氰酸酯(PPDI)、扩链剂为1,4-丁二醇(BD)时,不同结构的多元醇制备PU的耐热性从优到劣依次为聚己内酯二醇体系,聚己二酸1,4-丁二醇酯体系,聚碳酸酯二醇(PCD)体系,聚四亚甲基醚二醇体系;当多元醇选取PCD、扩链剂为BD时,不同结构的二异氰酸酯制备PU的耐热性从优到劣依次为1,5-萘二异氰酸酯(NDI)体系,对苯二异氰酸酯(PPDI)体系,3,3'-二甲基联苯-4,4'-二异氰酸酯(TODI)体系,4,4'-二苯基甲烷二异氰酸酯(MDI)体系;TODI、NDI制备PU的动态力学性能优于PPDI和MDI制备的PU.     

一种高耐磨聚氨酯弹性体及其制备方法

<正>本发明公开了一种高耐磨聚氨酯弹性体由预聚体组分和扩链剂组分组成,其中预聚体先由聚酯或聚醚多元醇与二苯基甲烷二异氰酸酯(MDI)合成羟基封端的MDI改性多元醇,MDI改性多元醇再与甲苯二异氰酸酯反应制得;扩链剂组分为4,4’-二氨基-3,3’-二氯二苯甲烷、3,5-二甲硫基甲苯二胺或二乙基甲苯二     

聚醚型与聚酯型聚氨酯弹性体的性能研究

使用聚乙二醇(PEG)、聚四亚甲基醚二醇(PTMG)、聚己内酯(PCL)和4,4’-二苯基甲烷二异氰酸酯(MDI)合成了聚醚多元醇型和聚酯多元醇型热塑性聚氨酯弹性体(TPU)。研究了各种TPU中异氰酸酯指数(R0)、硬段浓度(Ch)、聚醚和聚酯的种类、摩尔质量及原料用量等对弹性体力学性能的影响;并且使用双酚A型环氧树脂NPEL-127改性了弹性体的耐热性。研究结果表明:TPU的硬度随着R0和Ch的增加而增加;聚醚型TPU中,随着软段中柔性链的增加,TPU的硬度下降而力学性能提高;聚酯型TPU中,随着聚酯和聚酯二元醇摩尔质量的提高,TPU的硬度和力学性能均有提高;聚酯型TPU的力学性能优于聚醚型TPU;环氧树脂改性使得聚醚型TPU耐热性提高。     

可瓷化PDMS改性聚氨酯泡沫复合材料的制备及其性能研究

硬质聚氨酯泡沫塑料具有低密度、低导热系数和优良的隔热保温性能,但耐热性较差,需提高其耐热性以满足应用要求。本文使用羟基硅油(PDMS)对聚氨酯进行改性,并添加低熔点玻璃粉、滑石粉和高岭土等填料,采用模压成型工艺制备可瓷化PDMS改性聚氨酯泡沫复合材料,研究了高岭土对可瓷化PDMS改性聚氨酯泡沫复合材料压缩强度、导热系数和耐热性能等的影响。结果表明:随着高岭土含量的增加,材料的密度增大,导热系数变大,压缩强度提高;SEM结果显示,800℃处理后材料表面生成一层陶瓷化连续相结构;XRD分析表明新生成的陶瓷相为α-石英和斜方锰顽辉石。因此,无机填料的添加有效地提高了硬质聚氨酯泡沫塑料的耐热性。     

结构阻燃型腰果酚基硬质聚氨酯泡沫的制备及性能研究

以三聚氰胺改性腰果酚基阻燃多元醇和异氰酸酯为主要原料,采用环戊烷为发泡剂,添加无卤阻燃膨胀型阻燃剂石墨(EG)、匀泡剂等制备无卤阻燃生物基硬质聚氨酯泡沫塑料。探讨结构阻燃型聚醚多元醇、阻燃剂的添加对生物基硬质聚氨酯泡沫的热性能、燃烧性能和力学性能的影响。结果表明,随着阻燃剂的增加,导热系数和固化时间增加;添加相同阻燃剂的泡沫样品其阻燃性能随着添加量的增加而增加,EG在提高氧指数方面优于聚磷酸铵(APP)和乙基膦酸二乙酯(DEEP),固体阻燃剂APP和EG在增加力学性能、热稳定性方面较液体阻燃剂DEEP效果好。     

环保型聚氨酯泡沫保温墙体材料的研究

本文采用水、异戊烷为发泡剂,通过与聚醚多元醇和二苯基甲烷二异氰酸酯(MDI)、多次甲基多苯基多异氰酸酯(PAPI)以及一些助剂的混合反应制得硬泡聚氨酯。并对产品的导热系数、抗压强度、泡沫密度、阻燃性等性能进行测试。经过实验比较得出,以异戊烷为发泡剂制备的硬泡聚氨酯材料,各项性能均最好,且符合环境保护的要求。     

以大豆油多元醇制备的硬质聚氨酯泡沫塑料的性能研究

用大豆油多元醇替代石化聚醚多元醇制备出了硬质聚氨酯泡沫塑料（RPUF）,考察了石化聚醚多元醇和大豆油多元醇的比例以及RPUF密度对RPUF性能的影响。结果表明,随着大豆油多元醇用量的增加,RPUF的冲击强度和压缩模量减小,压缩屈服点逐渐消失,玻璃化转变温度升高;但随着大豆油基RPUF密度的增加,其冲击强度、压缩模量和储能模量都得到了提高,压缩模量最高可达56.44 MPa。     

聚氨酯/三聚氰胺甲醛树脂复合泡沫热降解动力学研究

三聚氰胺甲醛树脂脱水后和多元醇混合,然后用异氰酸酯与混合物进行交联反应,生成聚氨酯/三聚氰胺甲醛树脂复合泡沫.热重分析结果表明,复合泡沫失重分为3个阶段,二苯基甲烷二异氰酸酯(MDI)型三聚氰胺甲醛树脂复合泡沫的第2阶段的失重峰温比甲苯二异氰酸酯(TDI)型三聚氰胺甲醛树脂复合泡沫的高.采用Kissinger法研究了该...     

Insulating rigid polyurethane foams from laurel tree pruning based polyol

The present work deals with the production of a natural polyol from laurel tree pruning waste, aiming the preparation of polyurethane foams. The obtained bio-polyol was characterized and applied into foams studying the influence of the isocyanate used and the addition of the physical blowing agent. The incorporation of the polyol allowed 40% polyol substitution for those foams in which TDI was used, and up to 60% using MDI. Apparent density, cell morphology, mechanical, and thermal properties were evaluated. Mechanical and thermal properties of the foams improve to a greater amount of polyol in the matrix. Specifically, the best thermal and mechanical properties (274.99 and 7275.91 kPa for compressive strength and Young Modulus, respectively) were obtained with 50% polyol substitution (0.63 R_NCO/OH). Foams showed small, well-defined cell morphology. Laurel derived polyol can be used for the preparation of foams using MDI, since the mechanical, and thermal properties are promising for obtaining insulation materials in the construction industry.     

Preparation and Characterization of Sustainable Polyurethane Foams from Soybean Oils

Polyol derived from soybean oil was made from crude soybean oil by epoxidization and hydroxylation. Soy-based polyurethane (PU) foams were prepared by the in-situ reaction of methylene diphenyl diisocyanate (MDI) polyurea prepolymer and soy-based polyol. A free-rise method was developed to prepare the sustainable PU foams for use in automotive and bedding cushions. In this study, three petroleum-based PU foams were compared with two soy-based PU foams in terms of their foam characterizations and properties. Soy-based PU foams were made with soy-based polyols with different hydroxyl values. Soy-based PU foams had higher T _g (glass transition temperature) and worse cryogenic properties than petroleum-based PU foams. Bio-foams had lower thermal degradation temperatures in the urethane degradation due to natural molecular chains with lower thermal stability than petroleum skeletons. However, these foams had good thermal degradation at a high temperature stage because of MDI polyurea prepolymer, which had superior thermal stability than toluene diisocyanate adducts in petroleum-based PU foams. In addition, soy-based polyol, with high hydroxyl value, contributed PU foam with superior tensile and higher elongation, but lower compressive strength and modulus. Nonetheless, bio-foam made with high hydroxyl valued soy-based polyol had smaller and better distributed cell size than that using low hydroxyl soy-based polyol. Soy-based polyol with high hydroxyl value also contributed the bio-foam with thinner cell walls compared to that with low hydroxyl value, whereas, petroleum-based PU foams had no variations in cell thickness and cell distributions.     

Physical properties of new polyurethanes foams from benzene polyols synthesized from erucic acid

High density triol‐based polyurethane (PU) foams were developed from aromatic triol isomers prepared from erucic acid. The triol monomers were crosslinked with 4,4′‐diphenylmethane diisocyanate (MDI) into PU foams. The foam's properties were studied by Fourier transform infrared (FTIR) spectroscopy, X‐ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). The foams were analyzed for closed cell content and compression strength. The effect of the benzene ring in the polyol structure on the physical properties of these new PU foams was compared with high density foams made from aliphatic polyols originating from canola oil. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

New foamed plastic based on polyetherols obtained from 6‐aminouracil,ethylene carbonate,and propylene oxide

Polyetherols with 1,3‐pyrimidine ring including both oxyethylene and oxypropylene groups were obtained in reactions of 6‐aminouracil with ethylene carbonate and propylene oxide. The structure of the products was analyzed by spectral methods. Some physical properties of polyetherols were investigated. The polyetherols were used as polyol components to obtain polyurethane foams. Some properties of the foams such as apparent density, absorption of water, linear dimensions stability, thermal resistance, and compression strength were investigated. The foams obtained show an improved thermal stability. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

脂肪族聚碳酸酯型聚氨酯软泡性能的影响因素

以自制的脂肪族聚碳酸亚乙酯二元醇和液化MDI为主要原料,制备了聚碳酸酯型聚氨酯软泡,并对发泡剂、异氰酸酯、稳定剂用量及操作工艺等对泡沫体性能的影响进行了讨论。结果表明,通过调节发泡剂、异氰酸酯、稳定剂用量等,可以得到密度在8~80kg/m3之间、压缩强度在10~108kPa之间的聚氨酯软泡。     

Development of a rigid polyurethane foam from palm oil

The reactions between polymeric diphenyl methane diisocyanate (polymeric MDI) and conventional polyols to produce foamed polyurethane products are well documented and published. Current polyurethane foams are predominantly produced from these reactions whereby the polyol components are usually obtained from petrochemical processes. This article describes a new development in polyurethane foam technology whereby a renewable source of polyol derived from refined–bleached–deodorized (RBD) palm oil is used to produce polyurethane foams. Using very basic foam formulation, rigid polyurethane foams were produced with carbon dioxide as the blowing agent generated from the reaction between excess polymeric MDI with water. The foams produced from this derivatized RBD palm oil have densities in excess of 200 kg/m³ and with compression strengths greater than 1 MPa. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 509–515, 1998     

高回弹、低密度环保泡沫用改性MDI的合成及其对制品性能的影响

采用低不饱和度、高相对分子质量、高活性聚醚多元醇,反应型增硬剂,反应型开孔剂和MDI型异氰酸酯为原料,研制出一种用于制备高回弹、低密度环保型泡沫的改性MDI,解决了当前改性MDI的模塑泡密度难以低于45kg/m3的技术问题。此改性MDI制备的高回弹泡沫在保证制品良好回弹性和硬度的前提下,密度最低可以降至38kg/m3。     

Development and Characterization of Water-Blown Polyurethane Foams from Diethanolamides of Karanja Oil

The present study focuses on the use of renewable resource, namely karanja oil for the development of polyurethane foams. The non-edible oil was chemically modified into the diethanolamide by hydroxylation followed by transamidation. The structure of the diethanolamide was confirmed by proton nuclear magnetic resonance spectroscopy, infrared spectroscopy and gas chromatography–mass spectrometry and used as polyol to prepare water-blown polyurethane foams. Polyurethane foams were produced with carbon dioxide as the blowing agent generated by the reaction between excess polymeric MDI with water. Foams were prepared by a hand mixing process which involved blending of the diethanolamide with polypropylene glycol, polymeric MDI, water, catalyst and surfactant. The hydroxyamide content, catalyst nature and molecular weight of polypropylene glycol were varied and the effect on the properties was studied. Foam rise time and other physical properties such as density, compression strength and flexural strength were evaluated. Optical microscopy was used to study the morphology to reveal the closed cell nature and other structure–property relationships.     

Rigid polyurethane foams from a soybean oil-based Polyol

Polyurethane (PU) rigid foams were synthesized by substituting a polypropylene-based polyol with soybean oil-based polyol (SBOP). All the soy-based foams maintained a regular cell structure and had even smaller average cell size than the control foams. The density of soy-based foams was within 5% of the controls, except that the density of foams from 100% SBOP was 17% higher. Soy-based foams also had comparable initial thermal conductivity (k value) and closed cell content, higher T_g and compressive strength. However, while foams from 50% SBOP showed similar increase in k value to the 0% SBOP foams, under accelerated aging conditions, the 100% SBOP foams aged faster. Gas permeation tests performed on PU thin films showed higher N₂ permeation for PU thin films made from SBOP which is believed to be the cause of accelerated thermal aging.