单组分聚氨酯弹性体的制备及性能

单组分湿固化弹性体因操作方便、性能优越被广泛应用,是聚氨酯密封胶和胶黏剂等产品中的重要组成部分。介绍了单组分湿固化弹性体的合成工艺,确定了各原料使用的最佳比例,并对反应过程中的多元醇种类、异氰酸基(—NCO)含量、空气湿度、潜固化剂种类以及填料加入量等条件进行了考察研究。结果表明,当预聚体中—NCO的质量分数为3.5%、合成预聚体使用的羟值为56的C3050A聚氧化丙烯三醇质量分数为20%、牌号为PTMG2000的聚四亚甲基醚二醇与牌号为DL2000D的聚氧化丙烯二醇的质量比为1∶3、潜固化剂使用牌号为AT-401的■唑烷、填料质量分数为25%时,得到的聚氨酯弹性体力学性能适中,便于施工且成本较低。     

低特征信号聚氨酯弹性体的合成方案及性能研究

以聚氧化丙烯二醇、聚四氢呋喃二醇和六亚甲基二异氰酸酯为主原料,制得异氰酸酯基（--NCO）封端的聚氨酯预聚体,再用三羟甲基丙烷作为交联剂将混合预聚体固化合成聚氨酯弹性体。通过设计正交实验调整了预聚体各组分的配比及抑烟剂、成炭剂、阻燃剂的用量,通过测试材料的力学性能、燃烧性能确定了最佳合成方案。其烧蚀速率达到0．3mm／s,红外光透过率为92．4％,可见光透过率为90．1％。     

聚氨酯种类对机械性能以及阻尼性能影响研究

分别以聚四氢呋喃醚二醇(PTMEG)、聚氧化丙烯二醇(PPG-1000)为软段,以二苯基甲烷二异氰酸酯(MDI-50、MDI-100LL),以及扩链剂1,4-丁二醇(BDO)、三羟甲基丙烷(TMP)为硬段,采用预聚体法制备了聚氨酯弹性体。并系统研究了聚氨酯体系中各组分的种类对材料机械性能和阻尼性能的影响。     

低不饱和度聚醚多元醇PU弹性体性能的影响因素

探讨室温固化低不饱和度聚氧化丙烯醚多元醇PU弹性体性能的影响因素。结果表明，预聚体中游离-NCO质量分数为O．08时，PU弹性体的固化速度快，综合物理性能较好；低不饱和度聚氧化丙烯醚多元醇的官能度和相对分子质量大，PU弹性体强伸性能好；相对分子质量为3000的低不饱和度聚氧化丙烯醚二醇／低不饱和度聚氧化丙烯醚三醇并用体系PU弹性体综合性能较好；扩链剂为MOCA、催化剂为醋酸苯汞的PU弹性体颜色较浅。     

基于不同软段的聚氨酯弹性体耐热性能研究

分别以聚己内酯二醇(PCL)、聚碳酸酯二醇(PCDL)、聚己二酸-1,4-丁二醇酯二醇(PBA)以及聚四氢呋喃二醇(PTMG)为软段,4,4'-二苯基甲烷二异氰酸酯(MDI)和1,4-丁二醇(BDO)为硬段,采用预聚体法合成4种基于不同软段的聚氨酯弹性体。通过机械性能测试、热失重分析、动态力学性能测试及不同温度下的力学性能分析,研究低聚物二醇种类对聚氨酯弹性体的力学性能和耐热性能的影响。结果表明,以聚酯多元醇作为软段制得的聚氨酯弹性体的耐热性要优于聚醚型;几种聚酯型聚氨酯弹性体中,PCL型聚氨酯弹性体的热稳定性以及不同温度下的力学性能保持率最高,耐热性最好;动态力学性能分析表明,在高弹态平台区PCL型聚氨酯的损耗因子较小,动态内生热较小,且储能模量下降较缓慢,动态力学性能最好。     

支化与交联型聚氨酯弹性体的合成与性能分析

为提高聚氨酯弹性体力学性能和耐热性,本文以聚己二酸二乙二醇酯二醇、二苯基甲烷二异氰酸酯和 1,4-丁二醇为原料,以聚氧化丙烯三醇（PPG-3）或丙三醇为支化单体,并通过调控其添加量（1%、3%和5%,相对于PDGA-2000的摩尔分数）,采用本体预聚物法合成支化或交联型聚氨酯弹性体。与线型聚氨酯相比,支化聚氨酯具有较高机械强度和耐热性。添加3% PPG-3所制备支化聚氨酯的拉伸强度提高170%（33.9MPa）,撕裂强度提高36%（90.7MPa）,维卡软化点温度为95.1℃;然而,5%的丙三醇引发交联结构的形成,交联型聚氨酯的拉伸强度提高154%（31.8MPa）,撕裂强度提高26%（84.4MPa）,维卡软化点温度为150.6℃。此外,PPG-3和丙三醇发挥聚氨酯软段和硬段相容剂的作用,抑制微相分离,使聚氨酯弹性体的橡胶平台增大。动态流变行为测试结果表明,支化和交联型聚氨酯弹性体具有更高的弹性模量和复数黏度。     

纳米蒙脱土插层聚氨酯改性环氧彩色地坪涂料的研制

采用聚氧化丙烯二醇(N-210)，甲苯二异氰酸酯(TDI)、有机纳米蒙脱土等为原料，制备了有机蒙脱土纳米插层聚氨酯预聚体，并以此对环氧树脂E-44进行化学改性，根据改性复合材料的力学性能等确定了纳米插层聚氨酯预聚体与环氧树脂配量范围，并以纳米插层聚氨酯改性的环氧树脂为基料，确定了地坪涂料各组分的最佳用量范围，研制出了一种高性能纳米插层聚氨酯改性环氧彩色地坪涂料。     

PPG型微孔聚氨酯弹性体抛光材料的制备及性能研究

以聚氧化丙烯二醇(PPG)、液化MDI为原料合成聚氨酯预聚体,然后与二胺扩链剂、发泡剂和氧化铈粉末混合制备微孔聚氨酯弹性体抛光材料。讨论了PPG相对分子质量及其相对分子质量分布对微孔聚氨酯弹性体抛光材料性能的影响。采用热重分析(TG)、动态力学分析(DMA)、扫描电镜(SEM)及万能拉力试验机等测试方法对微孔聚氨酯弹性体抛光材料的结构与性能进行了表征和分析。结果表明,当PPG的相对分子质量为1000、分子量分布指数为3.01时,所制备的微孔聚氨酯弹性体作为抛光材料使用时,具有良好的力学强度和耐磨性能。     

聚醚型高硬度聚氨酯弹性体的研制

采用聚氧化丙烯多元醇、二醇扩链剂和多异氰酸酯为原料，用一步法工艺制得一系列高硬度聚氨酯弹性体。讨论了多元醇组分平均每个羟基所对应的链段的相对分子质量(MOH)、平均官能度以及异氰酸酯种类对高硬度聚氨酯弹性体性能的影响。结果表明，采用液化MDI或粗MDI与聚氧化丙烯醚配合使用可以制得邵D硬度大于65的聚醚型高硬度聚氨酯弹性体。     

纳米插层聚氨酯改性环氧树脂性能研究

采用聚氧化丙烯二醇(N210和N220)、2，4-甲苯二异氰酸酯(TDI)、有机纳米蒙脱土(OMMT)等为原材料，分别制备了相应的聚氨酯预聚体和有机蒙脱土纳米插层聚氨酯预聚体，并以此对环氧树脂E44进行化学共聚改性，系统地研究了改性环氧树脂复合材料的力学性能等。研究表明，有机蒙脱土纳米插层聚氨酯能大幅度提高环氧树脂复合材料的韧性等，比相应的聚氨酯预聚体改性环氧树脂具有更好的效果。     

聚硅氧烷聚氨酯的合成与性能

氨基硅油、甲苯二异氰酸酯与相对分子质量为1000和2000左右的聚氧化丙烯二醇在无溶剂条件下制备了相应的两类氨基硅油改性聚氨酯。测试结果表明,采用无环境污染的该法制备的改性聚氨酯与文献报道的溶剂法制备的改性聚氨酯具有类似的改性效果,改性后的聚氨酯兼有有机硅和聚氨酯的特性。w(氨基硅油)=3%～15%时,有较明显的改性效果,且在w(氨基硅油)=10%时,两类改性聚氨酯都具有最佳综合性能,其伸长率较未改性的分别提高28 05%,52 38%,其表面水接触角分别提高了23°,25°,耐热性也有较大提高。     

不同结构聚醚改性硅油的制备与表征

以含氢硅油、（α-烯丙氧基,ω-羟基）聚氧乙烯聚氧丙烯醚（F-6）和（α-烯丙氧基,ω-甲氧基）聚氧乙烯聚氧丙烯醚（AEPM-1500）为原料,在氯铂酸催化剂作用下,通过硅氢加成反应,合成了一种聚醚改性硅油（AAMS）,并用红外光谱和核磁共振氢谱对其结构进行了表征。考察了反应时间、温度以及催化剂用量对Si—H转化率的影响,较佳合成工艺为：反应时间为6h、反应温度为105℃,氯铂酸用量为20μg/g,此时,Si—H的转化率可达94．6％;随着F-6与AEPM-1500的量之比的增大,产物AAMS水溶液的表面张力先降后升,浊点升高;当F-6与AEPM-1500量之比为4：1时,AAMS水溶液的表面张力可降至28．6mN／m,浊点为24℃。     

有机硅改性丙烯酸酯橡胶性能的研究

研究了改性方式、聚硅氧烷用量和聚合温度对有机硅改性丙烯酸酯橡胶性能的影响。结果表明，采用有机硅共聚改性（聚硅氧烷用量为１５％，聚合温度为５０℃），可显著改善丙烯酸酯橡胶的耐热性、耐寒性、耐水性及加工工艺性能，且硫化胶耐油性和力学性能变化不大，完全能满足作为耐热耐油密封件所用橡胶的要求     

Synthesis and properties of polyurethane modified with an aminoethylaminopropyl‐substituted polydimethylsiloxane. II. Waterborne polyurethanes

A series of polyurethane (PU) emulsions modified with aminosilicone were synthesized, based on 2,4‐toluene diisocyanate (TDI), poly(tetramethylene oxide) (PTMO), and dimethylolpropionic acid (DMPA) as a prepolymer which was chain‐extended with aminoethylaminopropyl polydimethylsiloxane (AEAPS) in an aqueous emulsion. Their chemical compositions, structures, bulk and surface properties, and emulsion morphologies were investigated using Fourier transform infrared spectrum analysis (FTIR), tensile and surface contact angle measurements, electron spectroscopy for chemical analysis (ESCA), water swellablity, an emulsion stability test, and transmission electron microscopy (TEM). It was shown that the PU emulsions were stable and the siloxane chains were enriched on the PU surface. The water resistance of the PU film increased but the bulk tensile properties of the PU film were not changed significantly with a small amount siloxane modification up to 6 wt %. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 295–301, 2001     

有机硅改性聚氨酯防污剂的合成与性能

以4,4'-二环己基甲烷二异氰酸酯(HMDI)、异佛尔酮二胺(IPDA)、聚己二酸乙二醇酯二醇(SP-2313)、聚二甲基硅氧烷(PDMS)等为主要原料,采用分步投料法合成了一种有机硅改性聚氨酯处理剂。与市购的两种合成革用防污处理剂进行了对比测试,该有机硅改性聚氨酯处理剂能够改善合成革表面触感,同时对日常生活中常见的污染源如口红、牛仔布等有明显的防护作用,非常适于作为电子保护套用合成革的表面处理。     

Contrasts in the surface activity of polyoxypropylene and polyoxybutylene-based block copolymer surfactants

Previous studies have shown that polyoxybutylene surfactant hydrophobes are less polar than polyoxypropylene hydrophobes. Polyoxyalkylene hydrophobes can be modified by ethoxylation to give terminal polyoxyethylene block hydrophilic groups. Polyoxybutylene/polyoxyethylene copolymer surfactants exhibit differentiated interfacial tensions, and wetting and foaming properties when compared to structurally equivalent polyoxypropylene/polyoxyethylene copolymers. There have been no reported comparisons, however, of polyoxybutylene/polyoxyethylene copolymers and polyoxypropylene/polyoxyethylene analogues in terms of fundamental parameters, such as critical micelle concentration, area per molecule at the interface, efficiency, and effectiveness. In one phase of this work, four polyoxybutylene/polyoxyethylene block copolymer surfactants were compared to structurally analogous polyoxypropylene/polyoxyethylene materials. Findings showed that polyoxybutylene/polyoxyethylene copolymers exhibited enhanced cotton wetting and lower surface and interfacial tensions compared to polyoxypropylene/polyoxyethylene analogues. Polyoxybutylene-based surfactants were typically one order of magnitude better in their ability to reduce surface tension at interface saturation. Polyoxybutylene/polyoxyethylene copolymers pack more efficiently at the interface, as evidenced by a smaller area per molecule at the interface. Critical micelle concentration values were also lower for polyoxybutylene/polyoxyethylene copolymers. A second phase of experiments focused on the surface activity of polyoxypropylene/polyoxyethylene triblock copolymers with higher molecular weight hydrophobes. Enhanced surface activity was found when compared to lower-molecular weight polyoxypropylene/polyoxyethylene copolymers.     

Surface Energy and Thermal Stability Studies of Poly(dimethyl siloxane)–Poly(alkyl(meth)acrylate) Copolymers

The correlation between the surface energy and thermal stability of polymers plays an important role in engineering of plastic materials. In this work, microstructural characteristics of copolymers of poly(dimethyl siloxane) with benzyl methacrylate, ethyl methacrylate, and methyl acrylate are correlated with their surface energy and thermal stability. The poly(dimethyl siloxane) segments in the copolymer chains affected the hydrophobic behavior. The surface energy of the synthesized copolymers decreased by increasing segments of alkyl methacrylates. The thermal stability of copolymers suggesting that heat resistance of poly(dimethyl siloxane) copolymers used in this correlation can be improved by adjusting the units of alkyl methacrylates in copolymers.     

Epoxidized pine oil‐siloxane: Crosslinking kinetic study and thermomechanical properties

In this study, a novel approach to toughen biobased epoxy polymer with different types of siloxanes was explored. Three different modified siloxanes, e.g., amine‐terminated polydimethyl siloxane (PDMS‐amine), glycidyl‐terminated polydimethyl siloxane (PDMS‐glycidyl), and glycidyl‐terminated polyhedral oligomeric silsesquioxane (POSS‐glycidyl) were used as toughening agents. The curing and kinetics of bioepoxy was investigated by differential scanning calorimetry and Fourier transform infrared spectroscopy. The mechanical, thermal, and morphological properties of the cured materials were investigated. Rheological characterization revealed that the inclusion of POSS‐glycidyl slightly increased the complex viscosity compared to the neat resin. The morphology of the cured bioresin was characterized by transmission electron microscopy and scanning electron microscopy. The inclusion of POSS‐glycidyl to bioepoxy resin resulted in a good homogeneity within the blends. The inclusion of PDMS‐amine or PDMS‐glycidyl was shown to have no effect on tensile and flexural properties of the bioresins, but led to a deterioration in the impact strength. However, the inclusion of POSS‐glycidyl enhanced the impact strength and elongation at break of the bioresins. Dynamic mechanical analysis showed that the siloxane modified epoxy decreased the storage modulus of the bioresins. The thermal properties, such as decomposition temperature, coefficient of linear thermal expansion, and heat deflection temperature were improved by inclusion of POSS‐glycidyl. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42451.     

硅氧烷处理纳米层状硅酸盐对膨胀阻燃聚乳酸性能的影响

采用4种经过不同表面处理剂改性的有机层状硅酸盐（Clay）与膨胀型阻燃剂复配阻燃聚乳酸（PLA）。通过熔融共混的方法制备阻燃PLA纳米复合材料,并通过极限氧指数、垂直燃烧、锥形量热测试和热失重分析对材料阻燃性能和热稳定性进行了研究,通过扫描电子显微镜对残炭形貌进行了分析。结果表明,加入经硅氧烷表面处理的Clay的PLA具有最好的热稳定性和阻燃性能;与不加Clay的阻燃PLA复合材料相比,极限氧指数从30.6 %提高至34.2 %,并且通过垂直燃烧UL 94 V-0级别,热释放速率峰值从283 kW/m2下降至199 kW/m2,下降幅度为30 %;残炭形貌分析结果显示,加入硅氧烷表面处理之后的Clay能够使残炭更加完整致密,从而提高了材料的阻燃性能。     

Studies on polyurethane protective surface material resistance to cavitation erosion

The polyurethane protective surface material, which were made from four different types of polyester and polyether polyol, have been studied with respect to their ultimate properties. The PTMG (polyoxytetramethylene glycol)- and PPG (polyoxypropylene giyco)-based polyurethane protective surface materials exhibited the best results. Use of JIPNs (joint interpenetrating polymer networks), prepared from combinations of polyurethnes with an epoxy adduct with coupling agents and talc, could clearly improve the adhesive strength resistance to water in negative pressure cavitation erosion (by determination with a rotating dish apparatus) and the adhesive strength resistance toward boiling water. The polyurethane protective surface material, which was composed of three separated layers, showed better resistance to cavitation erosion than an epoxy system, poly(methyl methacrylate), aluminum, steel, and different alloys in tests using the venturi tube and the rotating dish apparatus for simulated cavitation erosion, as well as in some power stations in actual field trials.