聚氨酯胶粘剂热稳定性研究进展

聚氨酯胶粘剂具有化学粘合力强、耐超低温、耐磨、耐溶剂等优点,在航天、建筑、电子工业等领域应用广泛。但是聚氨酯胶粘剂存在热稳定性差的缺陷,通过改性方法可以提高其热稳定性。围绕交联改性(与丙烯酸酯类单体、环氧类树脂及异氰酸酯三聚体共聚)、引入耐热基团(引入苯环、硅氧键、酰亚胺及碳硼烷)、与无机纳米材料(纳米二氧化硅、纳米黏土及纳米碳材料)复合这3种改性方法,综述了近年来国内外聚氨酯胶粘剂热稳定性的研究进展,并对提高聚氨酯胶粘剂热稳定性的研究方向进行了展望。     

聚氨酯／环氧树脂互穿网络聚合物相行为与粘接剪切性能的研究

制备了一系列聚氨酯／环氧树脂互穿聚合物网络ＰＵ／ＥＰＩＰＮｓ。由ＤＳＣ、ＴＭＡ和ＤＤＶ研究表明，ＩＰＮｓ在高温区存在单一的玻璃化转变温度Ｔｇ，ＩＰＮｓ的相行为与其粘接剪切强度相关。并确认接枝共聚物的存在增强了ＩＰＮｓ的互穿效应     

蓖麻油-丙烯酸酯改性的双组分水性聚氨酯胶粘剂研究

以聚醚多元醇(N220)、甲苯二异氰酸酯(TDI-80)、蓖麻油(C.O)、甲基丙烯酸甲酯(MMA)为主要原料,合成了蓖麻油改性的水性聚氨酯(WPUCA)复合乳液.向该复合乳液中加入固化荆,得到复合软包装用双组分改性水性聚氨酯胶粘剂.研究了蓖麻油的添加量以及丙烯酸酯和聚氨酯比例对改性后乳液及胶膜各项性能的影响,同时研究了多异氰酸酯固化剂用量及固化时间时胶粘剂粘结性的影响.实验结果表明,蓖麻油的添加量为3.0%(质量分数),PA、PU质量比为1:2,固化荆含量为6%(质量分数),固化时间为4h,胶粘剂的性能达到较佳.     

环氧—丙烯酸酯/聚氨酯互穿网络涂料

华中理工大学化学系研制一种环氧一丙烯酸酯／聚氨酯互穿网络涂料。这种涂料是以蓖麻油聚氨酯（PU），作为一种预聚物，由环氧一丙烯酸酯与乙烯基单体（P）为另一个预聚体。使用前将二者按一定的比例混合，加入适量的催化剂Sn盐及氧化还原引发剂即可。该涂料的PU预聚体和PV预聚体的制法如下：将蓖麻油用脱水剂脱水，然后在室温下将一＊cO广OH按2．1：1．0加入TDI中，充分搅拌反应1～Zh即得预聚体PU。将（甲基）丙烯酸与环氧树脂以摩尔比2：卫加入反应瓶中，并加入少量溶有对苯二酚的溶剂，充分搅拌，然后于室温下加入自制的活性催化…     

环氧大豆油改性水性聚氨酯胶粘剂

以聚氧化丙烯二醇、甲苯二异氰酸酯等为原料,以环氧大豆油为改性剂制备出环氧大豆油改性聚氨酯乳液,以该乳液配制出复合软包装膜用水性聚氨酯胶粘剂.用傅立叶变换红外光谱和粒度分析仪对乳液进行了表征,考察了聚氨酯乳液的稳定性及其胶膜的耐水性,研究了水性聚氨酯胶粘剂对几种复合薄膜的粘接性能.红外分析表明,环氧大豆油中的环氧基发生反应,形成了环氧大豆油改性水性聚氨酯.当环氧大豆油用量为4%～6%(质量分数,后同),聚氨酯乳液的稳定性较好,粘度较小,胶膜的吸水率不高,以该乳液配制的胶粘剂可满足复合软包装膜对粘接的要求.     

聚氨酯胶粘剂的制备、性能及其交联改性研究

以聚醚多元醇（GE210）、1，4一丁二醇和甲苯-2，4-二异氰酸酯（TDI）等为原料，以聚酯多元醇（P210）为交联剂，合成了具有不同异氰酸酯指数（R值）的线型和交联型两类溶剂型聚氨酯胶粘剂。通过红外谱图（FT-IR）表征了聚氨酯的结构，测定了所合成的聚氨酯胶粘剂的物理性能及其对皮革基材的粘接性能。结果表明，线型聚氨酯胶粘剂对皮革具有较强的粘接强度，且随着异氰酸酯指数的增加，粘接强度逐渐增强。加入交联剂后，随R值增大，胶粘剂的粘接强度也逐渐增大。在相同R值的情况下，交联型聚氨酯胶粘剂比线型聚氨酯胶粘剂的粘接强度有较大程度的提高。     

聚氨酯/环氧梯度互穿网络聚合物微观形貌及力学性能研究

设计了一种新的梯度组分分布数学模型,采用梯度因子和梯度层数控制梯度组分的分布,并采用逐层浇铸的方法制备了聚氨酯(PU)/环氧(EP)梯度互穿网络聚合物(IPNs)材料,研究了其微观形貌和力学性能.研究结果表明,随着梯度组分舍量沿梯度方向的变化,不同梯度单层的相结构和断裂特性也呈现相应的变化,逐渐由分散相向连续相转变.从中心层到表面层,梯度单层的弯曲模量逐层降低,挠度逐层增大,梯度IPNs的弯曲强度和模量低于普通IPNs,抗冲击性能高于普通IPNs.     

聚氨酯/环氧树脂互穿网络半硬泡沫的热稳定性

制备了聚氨酯/环氧树脂互穿网络半硬泡沫,通过热重分析(TGA)研究了其热分解,计算了各分解阶段的热分解反应动力学参数。结果表明,氮气中,互穿聚合物网络(IPN)泡沫根据环氧树脂含量不同其分解过程有2~3个失重阶段,随着环氧含量增加,第一阶段的失重率减小,第二阶段的失重率增大。IPN泡沫在第一、二两阶段总的热失重率低于纯聚氨酯泡沫及纯环氧树脂。环氧树脂含量为30%(质量分数,下同)时泡沫的热稳定性最好。预测IPN半硬泡沫在100℃氮气中失重5%时的热老化寿命可达2.4E7年,表明IPN泡沫具有很好的热稳定性。     

聚氨酯/环氧梯度互穿网络聚合物的弯曲行为

设计了一种新的梯度组分分布数学模型,采用梯度因子和梯度层数控制梯度组分的分布,并用逐层浇铸的方法制备了不同种类的EP/PU梯度互穿网络聚合物(IPNs)材料,对其弯曲行为进行了研究。研究结果表明,在相同质量比情况下,梯度IPNs的弯曲性能低于普通IPNs,并且梯度层数越多,梯度因子越大,弯曲性能越低,越容易发生弯曲变形。尽管弯曲性能有所降低,梯度IPNs的抗冲击性能要优于普通IPNs。     

三甲醇丙烷蓖麻油聚氨酯IPN的合成及性质

三甲醇丙烷蓖麻油聚氨酯互穿网络由２，４－甲苯二异氰酸酯与三甲醇丙烷在烯类单体（甲基丙烯酸甲酯，苯乙烯，丙烯酸丁酯等）作溶剂反应形成氨酯加成物的溶液，再与蓖麻油，过氧化苯甲酰和二丁基二月桂酸锡反应生成。研究了其合成条件，机械性能，电性能，耐水及耐油性能等。结果表明，其邵氏Ａ硬度可达８８，拉伸强度最高可达１５．１８ＭＰａ，断裂伸长在１２０％－１８０％，永久形变在２％以下，耐水耐油性能良好，同时，其体积     

Preparation,damping and thermal properties of potassium titanate whiskers filled castor oil-based polyurethane/epoxy interpenetrating polymer network composites

A series of potassium titanate whiskers (PTW) filled castor oil-based polyurethane (PU)/epoxy resin (EP) interpenetrating polymer network (IPN) composites were prepared. The damping properties, thermal stability as well as tensile strength of the IPN composites were studied systematically in terms of composition. Results revealed that the addition of PTW can significantly improve the damping properties of pure PU/EP IPN and can improve the thermal decomposition temperature. Tensile tests showed that the tensile strength of the IPN composites was improved after the incorporation of PTW. It is expected that the PTW filled IPN composites may be used as structural damping materials.     

Synthesis and characterization of castor oil based polyurethane-polyacrylonitrile interpenetrating polymer networks

A series of interpenetrating polymer networks (IPNs) of castor oil based polyurethane/polyacrylonitrile (PU/PAN: 80/20, 60/40, 50/50, 40/60 and 20/80) were synthesized by condensation reaction of castor oil with methylene diisocyanate and acrylonitrile, employing benzoyl peroxide (BPO) and ethylene glycol dimethylacrylate (EGDM) as initiator and crosslinkers respectively. The physical, chemical, optical and some of the mechanical properties of PU/PAN were studied. Phase stabilization in IPNs was investigated by wide angle X-ray (WAXS) profile analysis. Variation of crystal size distribution was studied in these polymer networks. Paper presented at the 5th IUMRS ICA98, October 1998, Bangalore     

接枝和非接枝聚氨酯/环氧树脂互穿网络聚合物的制备及其性能

采用分步法分别制备了接枝和非接枝聚氨酯(PU)/环氧树脂(EP)互穿网络聚合物(IPNs),研究了不同配比对材料力学性能和热性能的影响。红外结果显示接枝聚氨酯/环氧树脂互穿网络聚合物分子间形成了氨基甲酸酯的接枝结构;力学性能测试结果表明,聚氨酯的引入显著地提高了材料的力学性能,当m(PU)∶m(EP)=15∶85时,接枝聚氨酯/环氧树脂互穿网络聚合物的拉伸和冲击强度达到最大值(分别为36.7MPa和22.39kJ/m2),当m(PU)∶m(EP)=10∶90时,非接枝互穿网络聚合物拉伸和冲击强度达到最大值(分别为27.8MPa和19.34kJ/m2);TGA结果证实接枝互穿网络聚合物的热稳定性明显优于非接枝互穿网络聚合物。     

Morphologies and properties of polyurethane/epoxy resin interpenetrating network nanocomposites modified with organoclay

Polyurethane/epoxy resin interpenetrating network nanocomposites containing various contents of organophilic montmorillonite (oM-PU/EP nanocomposites) were prepared by a sequential polymeric technique and an in situ intercalation method. Transmission electronic microscopy and scanning electronic microscopy analysis showed that the interpenetrating process of PU and EP increases the exfoliation degree of organophilic montmorillonite (oMMT), and that oMMT improves the compatibility and phase structure of polyurethane/epoxy resin interpenetrating polymer networks (PU/EP IPNs). Tensile test, differential scanning calorimetry and thermal gravity analysis proved that the mechanical and thermal properties of the oM-PU/EP nanocomposites are superior to those of the pure PU and PU/EP IPNs.     

Damping analysis of polyurethane/epoxy graft interpenetrating polymer network composites filled with short carbon fiber and micro hollow glass bead

A series of short carbon fiber (CF) and micro hollow glass bead (HGB) filled polyurethane (PU)/epoxy resin (EP) graft interpenetrating polymer network (IPN) composites were prepared. The damping properties, thermal stability properties as well as tensile and impact strength of IPN composites were studied systematically. Results revealed that the addition of short carbon fiber and micro HGB can significantly improve the damping properties of pure PU/EP IPN and can improve the thermal decomposition temperature. Mechanical tests showed that the tensile strength of the IPN composites could be improved after the incorporation of short carbon fiber and micro HGB, while the impact resistance of the composites was impaired after the addition of micro HGB. It is expected that the carbon fiber and micro HGB filled IPN composites may be used as structural damping materials.     

The properties of polyurethane hybrid materials based on castor oil

The goal of this work was to investigate the properties of environmentally friendly, castor oil based polyurethane hybrid materials with titanium(IV) oxide nanoparticles, as a filler, and different types of diisocyanate (toluene diisocyanate and isophorone diisocyanate). In the sample synthesis, different ratios of the reactive groups (NCO/OH), r, were used (1, 1.15 and 0.92). In the composite preparation, only toluene diisocyanate was used, and the filler particles were premixed in a glass vessel with the castor oil polyol before the reaction with diisocyanate. For all the composite samples, the r value was 1. Polyurethane formation was confirmed by ATR-FT-IR by detecting the urethane band at 1515 cm⁻¹. It was determined that the hydroxyl groups had reacted because the broad band corresponding to the OH groups (3400 cm⁻¹) was not detected or detected at a reduced intensity depending on the r value. As was expected, the presence of the unreacted NCO groups was detected only for samples with r > 1 (band at 2300 cm⁻¹, which corresponds to the existence of these groups). The dynamic mechanical measurements were performed at a temperature range from −50 °C to 100 °C at different frequencies. For investigation of reinforcement effect of filler on polymer matrix, tensile testing was applied. The glass transition temperature, T_g, was determined by DSC measurement. It was estimated that the T_g of the samples decreased as the nanofiller content increased due to the changes in the segmental mobility influenced by the interaction between the nanoparticles and polymer chains.     

Synthesis and characterization of polyurethane/polybutyl methacrylate interpenetrating polymer networks

A series of castor oil based polyurethane (PU) and poly (butyl methacrylate) (PBMA) interpenetrating polymer networks (IPNs) (PU/PBMA; 80/20, 60/40, 50/50, 40/60 and 20/80) were prepared by sequential polymerization method using toluene diisocyanate (TDI), dibutyl tin dilaurate (DBTL) as catalyst and ethylene glycol dimethacrylate (EGDM) as crosslinker. Tensile strength, percentage elongation at break and surface hardness; FTIR and optical properties of the IPNs are reported. Thermo gravimetric analyzer (TGA) studies of the IPNs are performed in order to establish their thermal stability. TGA thermogram shows that the thermal degradation of IPN was found to proceed in three steps. The microcrystalline parameters such as crystal size (N) and lattice disorder (g in%) of IPNs have been estimated using wide angle X-ray scattering (WAXS) studies. The surface morphology of the IPNs has been studied using scanning electron microscope (SEM).     

蓖麻油基聚氨酯的制备及其性能研究

采用可再生的蓖麻油、甘油、TDI为原料,合成出端-NCO的蓖麻油基聚氨酯(PU)预聚体.对预聚体中NCO的含量进行了测定,并采用FT-IR对材料进行了定性分析;采用TG对蓖麻油基PU膜的热性能进行分析,并对固化后的材料力学性能进行了测试.结果表明:蓖麻油基PU预聚体的NCO含量在5.25%～4.93%时,体系在-18～40 ℃能固化成膜,且成膜物具有较好热学性能和力学性能.     

Interpenetrating polymer networks based on polyol modified castor oil polyurethane and poly(2-hydroxyethylmethacrylate): Synthesis, chemical, mechanical and thermal properties

Interpenetrating polymer networks (IPNs) of glycerol modified castor oil polyurethane (GC-PU) and poly[2-hydroxyethylmethacrylate] (PHEMA) were synthesized using benzoyl peroxide as initiator and N,N-methylenebis acrylamide as crosslinker. GC-PU/PHEMA interpenetrating polymer networks were obtained by transfer moulding. These were characterized with respect to their resistance to chemical reagents and mechanical properties such as tensile strength, per cent elongation and shore A hardness. Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) were undertaken for thermal characterization. The changes in NCO/OH ratio and GC-PU/PHEMA composition on the properties of the IPNs were studied.