微波液化木材及聚醚多元醇的制备

以醇解的聚酯(PET)饮料瓶为液化剂,甘油作辅助液化剂,微波辅助加热,用2.5%H2SO4催化液化木材。分别讨论了微波功率、液固比/反应时间和温度对液化率的影响。结果表明,在微波功率500 W,反应时间15 m in,温度150℃,液固比为4的条件下,木材液化率99.16%。以此液化物为起始剂,选用双金属氰化物MMC催化环氧丙烷开环聚合,通过改变环氧丙烷的用量制备了不同聚醚多元醇,并采用傅里叶变换红外(FT-IR)、凝胶色谱(GPC)及热示差扫描(DSC)等分析手段对起始剂和不同聚醚多元醇的结构、分子质量分布和耐热性进行了对比表征。研究表明聚醚多元醇的羟值、酸值、黏度随环氧丙烷用量增加减小,分子质量分布随之变窄,热稳定性下降。     

Green polyurethane from dimer acid based polyether polyols: Synthesis and characterization

In this study, dimer acid (DA) obtained from waste soybean oil was used together with propylene oxide (PO) to obtain novel polyether polyols [prepolymers for polyurethanes (PUs)] through ring‐opening polymerization reaction. The average molecular weight of polyols was estimated by gel permeation chromatography and titration method. The substantial reaction between DA and PO was evident from FTIR and nuclear magnetic resonance spectroscopy. Subsequently, the polyols were reacted with chain extender [ethylene glycol, (EG)] and 4, 4 ‐ Diphenylmethane diisocyanate (MDI) to prepare green PUs. The effect of molar ratio variation of EG and MDI with a fixed amount of polyols was estimated by measuring hydrophobicity and mechanical strength of PUs. The molar ratio such as 1 : 4 : 5.7 of polyol : EG : MDI was found to exhibit maximum hydrophobicity and improved mechanical strength that were comparable with typical PU sample prepared from commercially available polyol, such as polypropylene glycol. FTIR spectroscopic analysis confirmed the chemical changes and possible crosslinking in PUs. Thermalgravimetric analysis and differential scanning calorimetry analysis also showed substantial thermal stability of the green PUs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41410.     

支化结构不饱和聚酯的合成及性能研究

以乙二醇、季戊四醇(丙三醇)、反丁烯二酸为原料合成了含支化结构的不饱和聚酯(RP),对产物进行了红外表征,并通过GPC、DSC和TGA测试对其性能进行了研究。结果表明,季戊四醇(丙三醇)用量为反丁烯二酸物质的量的5%为宜,最佳反应温度为190～200℃,RP树脂数均分子质量为线形UP树脂的5倍左右。RP树脂相比UP树脂固化快,其最大放热温度、热稳定性和冲击性能均有所提高,其中冲击强度提高33%。此外,丙三醇型RP树脂较季戊四醇型反应易于控制,反应程度高。     

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     

Comparison of Adipic Versus Renewable Azelaic Acid Polyester Polyols as Building Blocks in Soft Thermoplastic Polyurethanes

In this study, novel polyester diols of 2000 molecular weight (MW) were synthesized by reacting azelaic acid (AZ) with 1,3‐propanediol (1,3‐PDO) and diethylene glycol (DEG) in the esterification reaction catalyzed with a small amount of butyltintris(2‐ethylhexanoate). As a reference, polyester polyols of 2000 MW were synthesized from adipic acid (AA) with 1,3‐PDO and DEG. The properties of polyester polyols were evaluated. The polyester polyol based on AZ and 1,3‐PDO is 100 % renewable polyol; 1,3‐PDO used in the syntheses is renewable product produced by fermentation process of sugar. Both 1,3‐PDO‐polyester polyols exhibited crystalline transition above room temperature, while DEG‐polyester polyols were liquid at room temperature. The polyester polyols were chain‐extended with 4,4′‐diphenylmethane diisocyanate (Mondur M) and 1,4‐butanediol (BDO) to form thermoplastic polyurethanes (TPU). TPU were evaluated for mechanical and water resistance properties, and their morphology were studied via differential scanning calorimetry (DSC), Fourier transform infrared (FTIR), and atomic force microscope (AFM). TPU based on azelate and adipate polyols were relatively soft elastomeric materials with high melting temperatures. AFM analyses of TPU indicated better phase separation in 1,3‐PDO polyester polyols with the highest phase separation observed in TPU based on 1,3‐PDO/azelaic acid polyols. Water resistance of TPU based on azelate polyols was improved as compared to TPU based on adipate polyols.     

蓖麻油酸基聚酯多元醇的合成研究

以可再生资源蓖麻油制备的蓖麻油甲酯、己二酸、乙二醇为原料,钛酸四正丁酯为催化剂,经酯化、缩聚合成蓖麻油酸基聚酯多元醇,考察了反应时间、催化剂、蓖麻油甲酯对聚酯多元醇热稳定性能的影响,采用凝胶色谱(GPC)、红外光谱仪(IR)、示差扫描量热仪(DSC)对蓖麻油酸基聚酯多元醇的相对分子质量、结构、热稳定性进行了系统的表征。实验表明,在醇酸(己二酸∶乙二醇)比为1.15、催化剂质量分数0.04%～0.05%、温度180℃,真空缩聚2h的条件下,制得相对分子质量为2600～3800、分布指数(PDI)为1.89～2.44的不同蓖麻油酸含量的聚酯多元醇,蓖麻油酸基聚酯多元醇的熔点随着蓖麻油酸含量的增加而降低。     

Polyurethane modified with 3‐aminopropyltriethoxysilane as wool antifelting agent

A wool antifelting agent containing polyurethane modified with 3‐aminopropyltriethoxysilane (APTES) was synthesized. Firstly an isocyanate ( NCO) group ended prepolymer was gained by a hydrogen shift reaction between isophorone diisocyanate (IPDI) and poly (propylene oxide triol) (PPT), and then NCO‐group of the prepolymer was blocked by 3‐aminopropyltriethoxysilane to form a precursor PPT‐[Si(OEt)₃]₃. After that a sol of the precursor was prepared for an antifelting agent. During heating the sol gelled and formed inorganic–organic hybrid film that was characterized by using FTIR and TGA. And then the wool fabric samples were treated with sol by pad‐dry‐cure process at different curing temperature (120, 140, and 160°C). The antifelting effects of different curing temperatures were compared. The results indicated that the new agent could endow a better antifelting effect with the low curing temperature at 120°C and 3 min. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

原材料对聚氨酯硬泡抗压性能的影响

以环氧丙烷聚醚多元醇、苯酐聚酯多元醇、多苯基甲烷多异氰酸酯PM-200、发泡剂一氟二氯乙烷(HCFC-141b)、泡沫稳定剂硅油AK-8801等为主要原料,采用一步法合成了聚氨酯硬泡,考察了不同种类多元醇及其配比、发泡剂、泡沫稳定剂种类及用量等对聚氨酯硬泡抗压性能的影响。结果表明:高羟值、高官能度的环氧丙烷聚醚多元醇可提高泡沫的压缩强度,且当环氧丙烷聚醚多元醇4110为100份,并加入20份左右苯酐聚酯多元醇580及10份左右聚醚403,泡沫稳定剂用量1～2份,发泡剂水用量0.5～1份,HCFC-141b用量30～35份,催化剂用量0.5～1.5份时,所得聚氨酯硬泡性能较好。     

Synthesis and properties of aliphatic polycarbonates derived from carbon dioxide,propylene oxide and maleic anhydride

Terpolymerization of carbon dioxide (CO₂) with propylene oxide (PO) and maleic anhydride (MA) was successfully carried out using supported zinc glutarate catalyst. Consequently giving high molecular weight poly(propylene carbonate maleate) (PPCMA) in a very high yield (72.5 g polymer/g catalyst). The resulting terpolymers were fully characterized by FTIR, ¹H NMR, ¹³C NMR, and wide‐angle X‐ray diffraction (WAXD) techniques. NMR measurements showed that PPCMA had an almost alternating structure for the components of carbon dioxide and PO. The influence of molecular weight and MA content on the properties of PPCMA was also investigated. Differential scanning calorimetry (DSC) measurements revealed that the glass transition temperature (T_g) of PPCMA increased with increasing molecular weight. Thermogravimetric analysis (TGA) indicated that PPCMA51 exhibited a very high decomposition temperature (263°C) due to the introduction of the double bond of MA into the backbone of terpolymer. The terpolymers with double bonds can be readily subjected to crosslinking reaction in high temperature to give a slightly crosslinked PPCMA, which exhibit superior thermal stability. Tensile tests also showed that the mechanical properties of PPCMA increased with increasing molecular weight. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

低不饱和度聚醚多元醇伯羟基含量的提高

首先采用自制的双金属氰化物络合催化剂，制备了低不饱和度、高相对分子质量聚氧化丙烯多元醇，然后与用传统碱催化制备的未经后处理的聚醚多元醇按一定比例混合，用环氧乙烷封端，经精制，得到高活性聚醚多元醇。所得聚醚二醇及聚醚三醇的不饱和度小于0.010mmol/g，伯羟基摩尔分数大于65%。     

低相对分子质量聚氧化乙烯的聚合研究

用自制氨钙催化剂合成低相对分子质量的聚氧化乙烯(PEO),用主成分分析法分析了环氧乙烷用量、溶剂用量、反应温度和反应时间对产物的相对分子质量的影响,并用红外光谱、DSC对产物进行了表征,确认为聚氧化乙烯均聚物。实验结果表明,环氧乙烷74 g、溶剂2.5 L、反应温度25℃、反应时间7 h时,收率达99.1%,相对分子质量为33.1万。     

Study of the effect of hyperbranched polyols on cationic UV curable coating properties

Cycloaliphatic epoxide‐based cationic UV curable coatings containing three different hyperbranched polyols (HBPs) were systematically formulated and characterized. Polyether polyols were found to deter epoxide conversion under low UV intensity. For high UV intensity, the cycloaliphatic epoxide conversion increased with polyol content. Coatings with HBPs had better flexibility and solvent resistance than those containing a reference triol. Compared to the triol and polyester HBPs, polyether HBPs imparted lower T_g and hardness but a better flexibilizing effect to the coatings. At higher R values, the coating solvent resistance decreased except for those with one polyether HBP. A two‐peak phenomenon was discovered in the residual thermal reaction heat curve after photoDSC experiments. These two peaks were found to be related to the thermal relaxation behavior of the photocured inhomogeneous film, and the reactivation and reaction of the ‘trapped living cationic species’. The capability of the polyol to lower the high‐temperature‐peak temperature corresponded well with the flexibilizing ability. Copyright © 2006 Society of Chemical Industry     

Phosphorus‐containing epoxy resins: Thermal characterization

Three novel aromatic phosphorylated diamines, i.e., bis N,N′‐{3‐[(3‐aminophenyl)methyl phosphinoyl] phenyl} pyromellitamic acid (AP), 4,4′‐oxo bis N,N′‐{3‐[(3‐aminophenyl)methyl phosphinoyl] phenyl}phthalamic acid (AB) and 4,4′‐hexafluoroisopropylidene‐bis N,N′‐{3‐[(3‐aminophenyl)methyl phosphinoyl] phenyl}phthalamic acid (AF) were synthesized and characterized. These amines were prepared by solution condensation reaction of bis(3‐aminophenyl)methyl phosphine oxide (BAP) with 1,2,4,5‐benzenetetracarboxylic acid anhydride (P)/3,3′,4,4′‐benzophenonetetracarboxylic acid dianhydride (B)/4,4′‐(hexafluoroisopropylidene)diphthalic acid anhydride (F), respectively. The structural characterization of amines was done by elemental analysis, DSC, TGA, ¹H‐NMR, ¹³C‐NMR and FTIR. Amine equivalent weight was determined by the acetylation method. Curing of DGEBA in the presence of phosphorylated amines was studied by DSC and curing exotherm was in the temperature range of 195–267°C, whereas with conventional amine 4,4′‐diamino diphenyl sulphone (D) a broad exotherm in temperature range of 180–310°C was observed. Curing of DGEBA with a mixture of phosphorylated amines and D, resulted in a decrease in characteristic curing temperatures. The effect of phosphorus content on the char residue and thermal stability of epoxy resin cured isothermally in the presence of these amines was evaluated in nitrogen atmosphere. Char residue increased significantly with an increase in the phosphorus content of epoxy network. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 2235–2242, 2002     

The role of polyol reaction catalysts in the cure kinetics and mechanical behavior of polyurethane adhesives

ABSTRACT

Polyurethane is one of the most versatile and commonly applied polymers in the world. Its properties are strongly dependent on the polyol/isocyanate structures and NCO:OH ratio, among other parameters. Additionally, the polyol structure is affected by the catalyst used for the reaction and production. The catalyst may indirectly affect the curing kinetics and mechanical strength of the PU, due to changes of polyol properties. This work evaluates the effects of two catalysts on the polyol structure and thus the effect of these polyol changes on the curing kinetics and mechanical strength of a PU adhesive. Two polyols were synthetized using the same hydroxyl-containing molecules derived from renewable natural sources, but with different types of catalysts (based on Sn or Li/Ti). The synthesized polyols were separately mixed with diphenylmethane diisocyanate in a 1.1:1 ratio of NCO to OH to form two bio-based PUs. The polyols were investigated by Fourier transform infrared (FTIR) spectroscopy, which showed the occurrence of some changes in the chemical groups of the polyol structure for both catalysts, as well as an influence on the curing kinetics. The mechanical behavior of the PU adhesives was characterized by dynamic mechanical analysis (DMA) and peeling tests. The results show a higher curing rate and higher peeling strength for the PU adhesives obtained using the Sn-based catalyst; both adhesives showed cohesive failure.     

异氰脲酸-苯酐基聚醚酯多元醇的合成及表征

以环氧丙烷（PO）、邻苯二甲酸酐（PA）为原料,三（2-羟乙基）异氰脲酸酯（THEIC）为起始剂,采用实验室自制双金属氰合配合物（DMC）为催化剂,合成具有类似于异氰酸酯三聚结构的异氰脲酸-苯酐聚醚酯多元醇。考察了聚合温度及催化剂的质量分数对聚合反应的影响。结果表明：在温度为135℃,催化剂的质量分数为440×10^-6的条件下,催化剂的催化效率和产率最高,诱导期和反应时间缩短,生产效率提高。通过对异氰脲酸-苯酐聚醚酯多元醇基与聚环氧丙烷聚醚基泡沫材料的氧指数测试,证明了异氰脲酸-苯酐聚醚酯多元醇能使制得聚氨酯泡沫材料的阻燃性提高。     

Effects of NCO/OH ratio and catalyst concentration on structure,thermal stability,and crosslink density of poly(urethane‐isocyanurate)

Poly(urethane‐isocyanurate)s were synthesized by reacting toluene diisocyanate and poly(propylene glycol) with various stochiometric ratios (1–3) in the presence of different concentrations of dibutyltin dilaurate (DBTDL) and ferric acetylacetonate (FeAA). The influence of the NCO/OH ratio and the catalyst type and concentration on the extent of urethane and isocyanurate formation were examined using Fourier transform IR spectroscopy. No trimer formation was observed in the presence of the FeAA catalyst. The percentage of the trimer group and the trimer/urethane content were found to be increased with increasing the stochiometric ratio or DBTDL concentration. The thermal decomposition of the copolyurethanes in an inert atmosphere was studied by means of thermogravimetry (TG). The TG curves showed three decomposition steps with the principal degradation temperature at about 355–385°C. The effects of the NCO/OH ratio, catalyst type and concentration, and heating rate on the thermal stability of the copolyurethanes were determined. The Flynn–Wall, Kissinger, and Ozawa methods were used to calculate the activation energies of thermal decomposition. The swelling behavior of solid copolyurethanes in toluene showed that, as the DBTDL concentration and/or NCO/OH ratio increased, the swelling ratio and average molecular weight between crosslinks were decreased whereas the crosslink density was increased. The sol fraction of solid copolyurethanes was examined and found to be reduced when the percentage of DBTDL or the stochiometric ratio was raised. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 963–972, 2003     

Curing kinetics of a rigid polyurethane foam formulation

The curing kinetics of a typical commercial formulation used in the manufacture of rigid polyurethane foams has been studied. The adiabatic temperature rise method was used, taking into account corrections for heat losses. A polymeric isocyanate was reacted with a stoichiometric amount of a polyether polyol, using dibutyltin dilaurate (DBTDL) as catalyst. For DBTDL < 2.6 mol m^?3, a strong inhibition of the catalyst took place, and the uncatalysed reaction played a major role. Second order kinetics gave a good fit for the whole conversion range. For DBTDL > 2.6 mol m^?3, the catalysed reaction took place. Second order kinetics were applicable up to the gel point, but then the rate slowed down severely. A first order dependence on the initial catalyst concentration was observed in the pre-gel region. The kinetics are discussed in terms of a modified version of the Van der Weij's mechanism. The heat of reaction was 17.6 kcal/NCO equivalent.     

A correlation for the estimation of critical micellization concentrations and temperatures of polyols in aqueous solutions

An empirical correlation is presented for the estimation of critical micellization concentrations (CMC) and critical micellization temperatures (CMT) for poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) copolymers in aqueous solutions. The CMC and CMT are expressed as a function of the polyol molecular weight, composition, and temperature (for CMC determination) or concentration (in the case of CMT). The correlation was developed from experimental CMT data for a set of 12 polyols that covered a wide range of molecular weights (2900–14600) and poly(ethylene oxide) contents (30–80 wt%) and is based on a simple expression for the standard free energy of micellization. Such a correlation should be useful to practitioners of the field as it allows easy prediction of CMC and CMT for a wide range of polyols with a minimal number of input parameters.     

Preparation of polyester polyols from unsaturated fatty acid

Oleic acid is a typical unsaturated fatty acid that is found widely in vegetable oils. The objective of this investigation was to produce a new type of oleic‐based polyol from oleic acid. Possible advantages of this approach include the production of high‐performance polyurethane materials from renewable resources and value‐added research for oleic acid. Oleic‐based polyols were synthesized by a three‐step process consisting of epoxidation and ring‐opening reaction, followed by esterification. The synthesized polyols appeared as a viscous liquid at room temperature with hydroxyl numbers from 307 to 425 mg KOH/g. Preparation of polyurethane foams using oleic‐based polyols and isocyanate was studied. An environmentally friendly blowing agent, HCFC‐141b, together with a small amount of water, was used. The synthesized foams were characterized by FTIR, SEM, and TG/DSC. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

CO_2/环氧丙烷共聚合成聚碳酸亚丙酯多元醇

利用双金属氰化物作为催化剂,催化CO2/环氧丙烷调节共聚制备聚碳酸亚丙酯多元醇(PPC),详细考察了催化剂用量、相对分子质量调节剂及其用量、CO2用量等对聚合的影响.研究发现PPC的相对分子质量与相对分子质量调节剂的用量成线性关系,可以根据需要合成具有规定相对分子质量的PPC树脂.最后提出聚合过程中碳酸丙烯酯可能按照解拉链的方式生成.