环氧树脂改性水性聚氨酯乳液的制备研究

传统的单一聚氨酯乳液存在耐水性和耐热性较差的缺点，目前最有效的方法是对其进行改性，以增强聚氨酯乳液胶粘剂的性能，使其应用更加广泛。控制异氰酸酯指数(R值)为3.5,以聚丙二醇(PPG1000)和甲苯二异氰酸酯(TDI)为主要原料合成聚氨酯预聚体，使用环氧树脂对聚氨酯乳液进行改性。用控制变量法将不同环氧值的环氧树脂和不同添加量的环氧树脂分别作为2个变量，讨论2个变量对乳液及胶膜性能的影响，按照相关标准对其性能进行了测试与表征。结果表明：在相同用量下，环氧树脂E-44的改性效果好于其他类型环氧树脂，E-44添加量为15%(质量分数)时，制备的改性材料性能最佳。     

环氧改性阳离子水性聚氨酯的制备及对纸张的表面处理

以异佛尔酮二异氰酸酯(IPDI)和己二异氰酸酯(HDI)为硬段,聚己内酯二醇(PCL1000)为软段,引入环氧树脂(E-44),采用原位聚合制得环氧改性阳离子水性聚氨酯乳液(EPUA)。通过傅里叶红外光谱(FT-IR)、耐介质性测试、接触角及力学性能测试研究了聚合物的构性关系。研究了E-44用量对聚合物及施胶性能的影响,并用扫描电镜(SEM)对纸张表面处理前后进行了表征。实验结果表明,当n(NCO)/n(OH)=1.3,m(MDEA)=10%,m(E-44)=12%时,乳液性能较佳,改性效果最好。在最佳聚合工艺条件下,施胶度为78s,湿强度达39%,耐折也达57次。随着m(E-44)增大,聚合物胶膜的耐介质性增强,吸水率从13.69%降至6.46%,吸甲苯率由121.5%降至74.8%,接触角由64.85°增大到116.49°,力学测试也表明拉伸强度随m(E-44)的增大得到改善,断裂伸长率减小。     

环氧树脂改性无溶剂聚氨酯-丙烯酸树脂复合乳液及其性能研究

采用原位聚合法,制备得到系列环氧树脂(E-44)改性的无溶剂阴离子聚氨酯/丙烯酸酯(WPUA)复合乳液。通过傅里叶红外光谱(FT-IR)、热失重分析(TGA)、耐介质性及力学性能测试讨论了E-44用量对WPUA乳液及其膜性能的影响。FTIR表明,E-44中的—OH和环氧基都参与了反应。TGA表明,E-44的加入明显改善了涂膜的热稳定性。另外当W(E-44)=7.6%时,涂膜吸水率为6.13%,吸乙醇率为49.78%,呈现良好耐介质性;且涂膜硬度可达2H,附着力达到0级,耐冲击性合格。     

改性阻燃环氧树脂胶粘剂的研制

以三聚氰胺聚磷酸酯(MPP)为阻燃剂,以聚酯型聚氨酯预聚体改性环氧树脂E-44为基体,制备改性阻燃环氧树脂胶粘剂.通过对改性基体材料进行电子探针(EPMA)以及冲击强度测试,对改性阻燃胶粘剂进行剪切强度、热稳定性以及阻燃性能测试,从而确定了聚氨酯与阻燃剂用量对胶粘剂性能的影响.结果表明:环氧树脂100份,聚氨酯预聚体30份,阻燃剂30份,制备的改性阻燃胶粘荆具有优异的韧性和阻燃性能,其拉伸剪切强度为21.3MPa,氧指数达29.6.     

通过环氧树脂后交联改性水性丙烯酸-聚氨酯

以三乙烯四胺(TETA)为后交联剂，合成了以环氧树脂(E-51)改性的丙烯酸一聚氨酯乳液，并用红外分光光度计来监控和表征环氧树脂E-51和固化剂TETA在成膜过程中的固化反应。观察了单组分乳液在聚合过程中以及储存时的稳定性。同时，讨论了环氧树脂对乳液的分散尺寸，涂膜的力学性能以及吸水性和吸甲苯率的影响。结果表明，当环氧质量分数低于20％时(以聚丙烯酸质量为基准)，乳液呈稳定态，并且拉伸强度和模量以及耐水、耐甲苯性随着环氧树脂质量分数的增加而增大，而断裂伸长率随之减小。     

一种新型航空导光面板基板材料的制备与性能研究

使用异弗尔酮二异氰酸酯(IPDI)和聚四氢呋喃醚二醇(PTMG)合成聚氨酯预聚体,再与环氧树脂E44反应,制备了含聚氨酯增韧软段的改性液体环氧树脂.以甲基六氢苯酐(MeHHPA)为固化剂,自制的二氮杂二环(DBU)对甲基苯磺酸盐为促进剂,固化成型,制备出一种无色透明的增韧环氧树脂板材.测试结果表明,与传统的航空导光面板基板材料有机玻璃(PMMA)相比,其光学性能相当,力学性能更加优越,而抗溶剂性、抗温度冲击性以及抗振动开裂性也大幅提高.     

环氧树脂改性水性聚氨酯胶粘剂的性能研究

通过丙酮法合成了一系列在软、硬段均含有离子基的水性聚氨酯分散液,采用共混法重点研究了环氧值,环氧树脂加入量以及R值(NCO/OH比)和离子基含量对水性聚氨酯乳液性能和胶粘剂粘接性能的影响。结果表明:选择E-44具有最佳的工艺和性能平衡,当E-44含量为3(wt%,质量分数),R值为1.3和离子基含量为1.15(wt%,质量分数)时所合成粘合剂的乳液稳定性,耐热性能和最佳的粘合性能。     

一种含多面低聚倍半硅氧烷的环氧树脂改性剂及性能研究

采用自制的γ-氨丙基笼型齐聚倍半硅氧烷(POSS-NH_2)与一小分子反应,合成了一种新型环氧树脂改性剂(POSS-NH-R),并以此对环氧树脂E-51进行改性.考察了不同添加量对复合环氧树脂的各项性能的影响,发现当添加量为25%时,改性效果最佳.     

超支化聚氨酯改性水性环氧树脂固化剂的制备与性能

以异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)和二乙醇胺(DEOA)为原料,合成出了超支化聚氨酯核HBPU-0;以IPDI、聚醚多元醇(N210)、DMPA等原料合成线型聚氨酯,然后将线型聚氨酯接枝到HBPU-0上,制备出超支化聚氨酯(HBPU);再以HBPU、环氧树脂E-44、丁基缩水甘油醚单封端的四乙烯五胺(TEPA-660a)为主要原料制备出超支化聚氨酯改性水性环氧树脂固化剂。用红外光谱、核磁共振、透射电镜、扫描电镜和热失重等方法表征和测试了聚合物的结构与性能,研究了HBPU含量对固化膜断面形貌、力学性能、热性能的影响。结果表明,当HBPU质量分数达到24%时,固化膜的综合性能最佳,此时冲击强度为23.4kJ/m2,拉伸强度为52.4 MPa,5%和50%的质量热损失温度分别为287.5℃和376℃,与未改性环氧树脂相比,柔韧性和耐热性均有显著提高。     

聚氨酯改性TDE-85/E-51环氧树脂的固化反应

以混合芳胺为固化剂,通过聚氨酯(PU)对4,5-环氧环己烷-1,2-二甲酸二缩水甘油酯(TDE-85)与二酚基丙烷缩水甘油醚(E-51)环氧树脂的混合树脂体系的改性,制备了高性能聚氨酯改性环氧树脂(PU/EP)。通过差示扫描量热法(DSC),确定了PU/EP体系的最佳固化条件,并探讨了PU/EP体系的固化反应动力学特征。研究结果表明,PU/EP体系的最佳固化条件为:25℃12h+150℃2h。PU/EP体系的固化反应活化能为69.18kJ/mol,反应级数为0.901。     

凝固科学技术与材料

从凝固科学与实践发展的角度介绍了当前凝固材料体系的基本框架和凝固科学主要发展阶段的基本理论。作为材料科学与工程的基本组成，凝固科学技术正在现代科学理论的基础上针对传统材料的改性提高和新材料的发展需求，以控形、控构、控性为目标开展优质铸件的定向、晶体生长、快凝、深过冷及各种新型和超常领域凝固过程的研究，并介绍了其中某些方面和展望了可能的发展趋势。     

Development and challenges of planning and scheduling for petroleum and petrochemical production

Production planning and scheduling are becoming the core of production management, which support the decision of a petrochemical company. The optimization of production planning and scheduling is attempted by every refinery because it gains additional profit and stabilizes the daily production. The optimization problem considered in industry and academic research is of different levels of realism and complexity, thus increasing the gap. Operation research with mathematical programming is a conventional approach used to address the planning and scheduling problem. Additionally, modeling the processes, objectives, and constraints and developing the optimization algorithms are significant for industry and research. This paper introduces the perspective of production planning and scheduling from the development viewpoint.     

江澳两地高校文创设计的协同研究与商业实践

目的 探索江门世遗文化的传承、发展和转化的新思路,践行国家在《粤港澳大湾区发展规划》纲要中要求江门承担与港澳地区文化创意合作与开发任务的分工。方法 与澳门高校紧密合作,开展专业培训课程,以开平碉楼为例,从人文视角开展设计研究,梳理开平碉楼的文化脉络,把世遗文化的元素和其背后的文化融入文创产品中,提升文创产品的附加值,推动当地文创产业结构的变革。结果 两地高校构建了稳定的科研团队,开设长期有效的设计培训课程,与景区建立了研究协作关系,帮助景区构建了一套产销研的商业模式。结论 以跨区域高校合作为平台,以文创产品为抓手,依托江澳两地的资源优势,可以构建江门世遗文化全新的品牌形象,最终推动开平世遗文化的活化。     

Error and uncertainty in modeling and simulation

This article develops a general framework for identifying error and uncertainty in computational simulations that deal with the numerical solution of a set of partial differential equations (PDEs). A comprehensive, new view of the general phases of modeling and simulation is proposed, consisting of the following phases: conceptual modeling of the physical system, mathematical modeling of the conceptual model, discretization and algorithm selection for the mathematical model, computer programming of the discrete model, numerical solution of the computer program model, and representation of the numerical solution. Our view incorporates the modeling and simulation phases that are recognized in the systems engineering and operations research communities, but it adds phases that are specific to the numerical solution of PDEs. In each of these phases, general sources of uncertainty, both aleatory and epistemic, and error are identified. Our general framework is applicable to any numerical discretization procedure for solving ODEs or PDEs. To demonstrate this framework, we describe a system-level example: the flight of an unguided, rocket-boosted, aircraft-launched missile. This example is discussed in detail at each of the six phases of modeling and simulation. Two alternative models of the flight dynamics are considered, along with aleatory uncertainty of the initial mass of the missile and epistemic uncertainty in the thrust of the rocket motor. We also investigate the interaction of modeling uncertainties and numerical integration error in the solution of the ordinary differential equations for the flight dynamics.     

Density and viscosity of tetralin and trans-decalin

New measurements are reported for the density and viscosity of tetralin and trans-decalin. The density was determined from room temperature to 60°C for tetralin and to 95°C for trans-decalin. The kinematic viscosity was measured up to temperatures slightly above 100°C. Our results improve upon the values recommended by the American Petroleum Institute for these liquids.     

The Candela and Photometric and Radiometric Measurements

The national measurement system for photometric and radiometric quantities is presently based upon techniques that make these quantities traceable to a high-accuracy cryogenic radiometer. The redefinition of the candela in 1979 provided the opportunity for national measurement laboratories to base their photometric measurements on optical detector technology rather than on the emission from high-temperature blackbody optical sources. The ensuing technical developments of the past 20 years, including the significant improvements in cryogenic radiometer performance, have provided the opportunity to place the fundamental maintenance of photometric quantities upon absolute detector based technology as was allowed by the 1979 redefinition. Additionally, the development of improved photodetectors has had a significant impact on the methodology in most of the radiometric measurement areas. This paper will review the status of the NIST implementation of the technical changes mandated by the 1979 redefinition of the candela and its effect upon the maintenance and dissemination of optical radiation measurements.     

Creation and motion of dislocations and fracture in metal and silicon crystals

By making a step on one surface ( ) of a rectangular small paralellepiped copper crystal, dislocations could be created by the molecular dynamic method. The dislocation created was not a complete edge dislocation but a pair of Heidenreich-Shockley partial dislocations. Each time a dislocation was created, the stress on the surface was released. Small copper crystals having a notch were pulled (until fracture), compressed and buckled by use of the molecular dynamic method. An embedded atom potential was used to represent the interaction between atoms. Dislocations were created near the tip of the notch. A very sharp yield stress was observed. The results of high speed deformations of pure silicon small crystals using the molecular dynamics are presented. The results suggest that plastic deformation may be possible for the silicon with a high speed deformation even at room temperature. Another small size single crystal, the same size and the same surfaces, was compressed using molecular dynamic method. The surfaces are {110}, {112} and {111}. The compressed direction was [111]. It was found that silicon crystals are possible to be compressed with a high speed deformation. This may suggest that silicon may be plastically deformed with high speed deformation.     

SMC／BMC的回收与再利用

SMC／BMC废弃物对工业及环境造成了很大影响，指出了SMC／BMC回收再利用的紧迫性。通过对目前国际上SMC／BMC回收再利用的3种典型途径优缺点的对比，参照国外SMC／BMC回收再利用的先进方法，对我国SMC／BMC回收再利用提供了可行的建议．