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采用甲苯二异氰酸酯(TDI)、聚乙二醇(PEG)。丙烯酸为原料,通过分子设计合成了带有双键的PU预聚体。用此预聚体与丙烯酸酯类单体进行共聚,通过测定乳液的粘度、粒径分布、胶膜的机械性能和热性能等方法,讨论了此预聚体用量对乳液和胶膜性能的影响。结果显示:随着预聚体用量的增加,共聚乳液的稳定性、粘度逐渐下降、乳液粒径有较大的变化;PUA共聚乳液胶膜的光泽度、附着力在预聚体用量为4%时最好,其胶膜的抗冲击强度及硬度均好于相应的PA乳液胶膜。 相似文献
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淀粉IPN型环保胶粘剂的合成 总被引:1,自引:1,他引:0
采用淀粉改性的聚醋酸乙烯酯(PVAc)乳液与聚氨酯(PU)预聚体交联制成了具有IPN(互穿网络聚合物)结构的胶粘剂。探讨了各原料的用量及反应温度等因素对该胶粘剂的制备及性能的影响。实验结果表明,制备该胶粘剂的适宜工艺条件为:氧化淀粉10.0g,水40.0g,聚乙烯醇(PVA)15.0g,PVAc25.0g,PU预聚体5.0g,乳化剂2mL,引发剂0.8g,扩链剂2mL,无机物填料5.0g,反应温度为65~85℃;由此制得的淀粉IPN型环保胶粘剂具有耐低温性好、耐水性佳、粘接强度高及无甲醛等优点,可用于层压板与纸塑、木塑复合材料的粘接。 相似文献
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<正>辽宁工程技术大学以三聚氰胺聚磷酸酯(MPP)为改性阻燃剂、以聚酯类聚氨酯(PU)预聚体改性环氧树脂(EP)为基体树脂,制备出一种阻燃性能优异的EP胶粘剂。当w(EP)=100份、w(PU预聚体)=30份和w(MPP)=30份时, 相似文献
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聚氨酯交联改性聚丙烯酸酯压敏胶的研究 总被引:3,自引:2,他引:1
采用溶液自由基共聚法合成了含有羟基的(甲基)丙烯酸酯共聚物(PA),采用预聚法合成了端-NCO基聚氨酯(PU)预聚体,然后将PA和PU预聚体混合均匀后制备PUA压敏胶。考察了n(-NCO)∶n(-OH)比例、不同相对分子质量(Mn)的聚丙二醇(PPG)和不同类型的聚醚合成的PU预聚体对PUA压敏胶性能的影响。实验结果表明,改性PUA压敏胶的剥离强度随着PU预聚体用量的增加而逐渐降低,最大降幅为8N/30mm左右,但残胶现象可消除;当n(-NCO)∶n(-OH)=3∶2、m(PA)∶m(PU)=10∶1且PPG的Mn为400时,所制取的PUA压敏胶的持粘性较未改性PA压敏胶提高了267%,但初粘性则有所降低;对Mn均为400的聚乙二醇(PEG)和PPG而言,由PEG400合成的PUA压敏胶比由PPG400合成的PUA压敏胶改性效果更好。 相似文献
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以聚氧化丙烯二醇(N-210)、甲苯二异氰酸酯(TDI)和氨丙基三甲氧基硅烷(A-1110)为主要原料,二月桂酸二丁基锡为催化剂,合成了含硅PU(聚氨酯)胶粘剂。研究结果表明:当反应温度为70~80℃、反应时间为4 h、R=n(—NCO)∶n(—OH)=(2.02~2.08)∶1.00、w(催化剂)=0.03%~0.05%(相对于胶粘剂质量而言)以及预聚体中w(—NCO)=2.5%时,合成的PU胶粘剂具有较好的力学性能(拉伸强度为3.23 MPa、断裂伸长率为387%)和粘接性能(剪切强度为3.11 MPa)。 相似文献
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采用预聚体一步法制备了单组分湿固化nano-SiO2(纳米SiO2)改性PU(聚氨酯)胶粘剂,并利用红外光谱(FT-IR)法、热失重分析(TGA)法、差示扫描量热(DSC)法和扫描电镜(SEM)等对nano-SiO2改性PU胶粘剂的性能进行了分析和探讨。结果表明:纳米粒子的存在使PU的氢键结构发生了变化;随着nano-SiO2含量的不断增加,改性PU胶粘剂的初始粘接强度和最终粘接强度均呈先升后降态势,并且在w(nano-SiO2)=1.2%(相对于PU预聚体质量而言)时相对最大,而且分别比纯PU胶粘剂增加了117%和108%;同时,与纯PU胶粘剂相比,用1.2%nano-SiO2制备的PU胶粘剂,其熔融温度和分解温度分别提高了2.67℃和2.92℃;当w(nano-SiO2)≤1.2%时,nano-SiO2在PU胶粘剂基体中的分散性相对较好。 相似文献
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无溶剂型单组分聚氨酯胶粘剂的研制 总被引:1,自引:1,他引:0
以聚醚二元醇(PPG)、改性MDI(4,4′-二苯基甲烷二异氰酸酯)、PAPI(多亚甲基多苯基多异氰酸酯)、1,4-BDO(1,4-丁二醇)和环保型PU潜固化剂等为主要原料,采用预聚体法制得无溶剂型单组分聚氨酯(PU)胶粘剂。研究结果表明:该胶粘剂的玻璃化转变温度(Tg)为-26.9℃;当R=n(-NCO)/n(-OH)=6.5~9.0、w(-NCO)=3.5%、w(环保型PU潜固化剂)=3%和聚醚二元醇是相对分子质量为1 000的PPG210时,PU胶粘剂的黏度适中、固化速率较快和可操作性良好,并且其强度和韧性俱佳。 相似文献
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以聚醚二元醇(DL-1000)、4,4′-二苯基甲烷二异氰酸酯(MDI)为主要原料合成端-NCO基PU(聚氨酯)预聚体;然后以γ-氨丙基三乙氧基硅烷(KH-550)对其进行嵌段共聚改性,并以3,3′-二氯-4,4′-二氨基二苯基甲烷(MOCA)/蓖麻油作为复合固化剂,制备出无溶剂型双组分有机硅改性PU胶粘剂。研究结果表明:硅烷键已引入PU胶粘剂中;随着KH-550含量的不断增加,胶粘剂的黏度增大、固化时间缩短、室温剪切强度下降且耐热性增强;通过调节不同KH-550含量,可制备出不同性能要求的胶粘剂;该胶粘剂的玻璃化转变温度(-45.9℃)相对较低,说明其耐寒性相对较好。 相似文献
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T. G. Maci -Agull J. C. Fern ndez-Garcí a A. Torr palau A. C. Orgil s Barcel J. M. Martí n-Martí nez 《The Journal of Adhesion》1995,50(4):265-277
Two hydrophilic and two hydrophobic fumed silicas of different characteristics were added to solvent-based polyurethane adhesives (PU). IR spectroscopy, contact angle measurements and rheology (viscosity measurements, determination of viscoelastic properties) were used to monitor the variation of properties of PU adhesives produced by addition of silica. Immediate (green) adhesion was determined by T-peel testing of halogenated synthetic rubber/PU adhesive/halogenated synthetic rubber joints. Silica addition produced a noticeable increase in the PU adhesive viscosity which can be related to the variation of viscoelastic properties. Viscosity of PU adhesives containing hydrophilic silica slightly increased with time after preparation; the increase was less significant in PU adhesives with hydrophilic silica. In the rheological studies, silica imparted shear thinning and negative thixotropy to PU adhesives due to a better dispersion of the silica in the polyurethane during shearing. The addition of silica produces an increase in the storage modulus (G') of PU adhesives, the values obtained being independent of the hydrophilic or hydrophobic nature of the fumed silica. The increase of G' and the changes in tan δ of PU adhesives containing silica corresponded to an improvement in the green adhesion properties of chlorinated rubber/PU adhesive/chlorinated rubber joints. In general, in disagreement with previous results,1 the presence of silica did affect the properties of solvent-based PU adhesives, but these properties were not dependent on the type of silica (hydrophobic or hydrophilic) used in this study. 相似文献
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Enhanced adhesion force based on microphase separation induced by complexation of ferric ions and polyurethane matrix 下载免费PDF全文
Xie Li Wei Li Xiaolin Wang Heling Guo Rongjie Wang Xuhong Guo Cuihua Li Xin Jia 《应用聚合物科学杂志》2018,135(17)
Waterborne polyurethane elastomer (WPU) has been widely used as a glue, but it still has some drawbacks, including a long cure time and weak adhesive force. In order to overcome these drawbacks, a new composite [PU/ferric ion complexation (Fe/PU)] with high adhesive strength was successfully prepared using ferric ion (Fe3+) as a complexing agent. Fourier transform infrared spectroscopy, differential scanning calorimetry, dynamic mechanical analysis, and tensile testing were used to characterize the chemical structure and mechanical properties of the as‐obtained composites. Introduction of the ferric ion induces a certain degree of microphase separation, resulting in better mechanical strength and interfacial adhesion. The mechanical properties of the PU composite with ferric ions are higher than that of pure PU. The adhesive strength of the 25%‐Fe/PU composite is 32.46 ± 3.1 MPa, exhibiting superior adhesive strength. The tensile strength was enhanced 34%, and the elongation was enhanced 23.6% compared to pure PU. Furthermore, the Fe/PU composite, coordinated with ferric ions, exhibits an enhanced storage modulus and reduced loss coefficient compared to PU. We can foresee that Fe/PU composites will play an important role in the building and engineering areas. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46069. 相似文献
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双(p-乙酰胺基苯氧基)二甲基硅烷改性聚氨酯涂层的耐热性 总被引:1,自引:0,他引:1
将双(p-乙酰胺基苯氧基)二甲基硅烷(AAPDS)作为改性扩链剂加入到聚氨酯(PU)涂层的室温固化体系中,以改善PU涂层的耐热性能。运用凝胶时间测定仪和热失重分析仪(TGA)对不同AAPDS加入量对PU涂层的凝胶时间和热失重温度的影响进行了研究;并测试了涂层在金属基体上的附着强度随高温处理时间的变化。结果表明,向涂层固化体系中加入占多元醇总质量4.5%的AAPDS后,固化凝胶时间由未改性时的14.0 min缩短至12.1 min,涂层的初始失重温度和失重5%的温度由273℃和278℃分别提高到296℃和302℃;在400℃下高温处理120 s后附着强度保留率达到80.9%,远高于未改性涂层的57.1%。 相似文献
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介绍了一步法合成新型不黄变聚氨酯(PU)胶粘剂的原料选择及合成工艺,并按相关的国际标准进行了性能测试。通过大量实验确定了聚己二酸丁二醇酯二醇(PBA)与异佛尔酮二异氰酸酯(IPDI)的最佳合成工艺路线是:反应时间为5~10min、反应温度为100~115℃、w(二月桂酸二丁基锡)为0.5%、R值为1.05、后熟化时间为4~10h和后熟化温度为120~140℃。由此制得的新型不黄变PU胶粘剂具有结晶度高、结晶速率快、内聚强度大、耐热性好、剥离强度高、稳定性好且综合性能优良等特点。 相似文献