光固化低黏度环氧丙烯酸酯的合成与性能研究

合成了可紫外光固化的低黏度环氧丙烯酸酯树脂,通过红外光谱、核磁共振氢谱、碳谱对树脂结构进行了表征;采用综合热分析仪(DSC-TG)对树脂固化膜的耐热性能进行了分析。结果表明,在树脂中添加活性单体时,随单体官能度的增加,固化膜的耐热性能增加,但双官能团单体的用量对固化膜的耐热性能没有明显影响。固化膜具有较好的耐热性,初始分解温度为330.7℃,玻璃化转变温度为76.9℃。所得树脂黏度仅为3~4Pa.s(60℃),为市售产品的1/3,附着力1级,硬度4 H,耐水性能优异,无需添加单体使用。     

紫外光固化环氧丙烯酸树脂的合成

环氧丙烯酸（ＥＡ）树脂在辐射固化领域中是一种重要的感光树脂,其中双酚Ａ型环氧树脂的应用最为广泛。本文着重研究了该种树脂的合成工艺,讨论了原料投料比、反应温度、催化剂及操作方法等因素对树脂性能的影响,并通过正交试验确定了最佳反应条件。     

Modified commercial UV curable elastomers for passive 4D printing

ABSTRACT

Conventional 4D printing technologies are realized by combining 3D printing with soft active materials such as shape memory polymers (SMPs) and hydrogels. However, the intrinsic material property limitations make the SMP or hydrogel-based 4D printing unsuitable to fabricate the actuators that need to exhibit fast-response, reversible actuations. Instead, pneumatic actuations have been widely adopted by the soft robotics community to achieve fast-response, reversible actuations, and many efforts have been made to apply the pneumatic actuation to 3D printed structures to realize passive 4D printing with fast-response, reversible actuation. However, the 3D printing of soft actuators/robots heavily relies on the commercially available UV curable elastomers the break strains of which are not suf?cient for certain applications which require larger elastic deformation. In this paper, we present two simple approaches to tune the mechanical properties such as stretchability, stiffness, and durability of the commercially available UV curable elastomers by adding: (i) mono-acrylate based linear chain builder; (ii) urethane diacrylate-based crosslinker. Material property characterizations have been performed to investigate the effects of adding the two additives on the stretchability, stiffness, mechanical repeatability as well as viscosity. Demonstrations of fully printed robotic finger, grippers, and highly deformable 3D lattice structure are also presented.     

Organically modified montmorillonites in UV curable urethane acrylate films

UV curable films were reinforced with an organically modified montmorillonite (MMT). The organically modified MMTs were prepared by an ion exchange process, in which sodium ions were replaced by alkyl ammonium ions. Cetyltrimethylammonium bromide (CTMA) modified clays gave rise to better intercalated clay morphology. The microstructures were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Physical properties were examined by real time infrared spectroscopy (RTIR), differential scanning calorimetry (DSC), photo-DSC, dynamic mechanical thermal analysis (DMTA). Some tensile properties were also reported. Thermal and mechanical properties were generally improved with nanoclay reinforcements. The effects of nanoclays on the properties of UV curable films are critically evaluated in this paper.     

混杂聚合有机硅改性环氧丙烯酸酯的研究

利用4,4'二苯基甲烷二异氰酸酯(MDI)与双羟基聚甲基苯基硅氧烷分子中的羟基反应制得-Nco封端的预聚体,再将该预聚体与环氧丙烯酸酯(EA)混合,得到有机硅化学改性环氧丙烯酸酯.在此基础上,以氨基树脂为固化剂,制得常温固化涂层;以2-羟基-2-甲基-l-苯基-l-丙酮(即1103)为光引发剂,在紫外光照射下制得常温光固化涂层;以氨基树脂为固化剂,1103为光引发剂,在紫外光照射下制得常温混杂聚合涂层.讨论了上述3种涂层的硬度随固化时间的变化,用热重一差热分析(TG-DTA)技术研究了三者的耐温性.结果表明:常温混杂聚合涂层的硬度随时间的延长增加得最快,光固化涂层次之,常温固化涂层最慢.3种涂层都能耐420℃左右的温度.     

紫外光固化环氧丙烯酸酯涂料的表征

研制了一种用于艺术玻璃彩绘的新型涂料——紫外线固化环氧丙烯酸酯涂料，主要通过涂膜硬度的测定、红外光谱(FTIR)和差示扫描量热分析法(DSC)研究了涂膜固化程度与辐射时间之间的关系，并用紫外光谱和红外光谱研究了引发剂及其引发涂膜固化的机理。     

UV固化水性环氧树脂的合成研究

对紫外光固化水性环氧树脂的合成工艺进行了研究,讨论了反应温度、反应时间、催化剂种类和用量,阻聚剂、羧基含量及固含量、中和剂等对水性环氧丙烯酸酯的合成和性能的影响。结果表明,合成环氧丙烯酸酯的最佳反应温度110℃,环氧丙烯酸酯与马来酸酐的最佳反应反应温度为80℃。反应时间均为5 h,三乙胺作催化剂,用量为反应物总质量的0.5%,对羟基苯甲醚作阻聚剂。实验表明,提出的紫外光固化水性环氧树脂的合成工艺可行,合成树脂具有水性特征,性能指标可以满足应用要求。     

UV光固化环氧丙烯酸酯耐磨涂料的研究

以E51和E44环氧树脂和丙烯酸为原料,制备了UV固化环氧丙烯酸酯耐磨涂料。不同光引发剂、稀释剂和助剂等对UV固化环氧丙烯酸酯涂料固化性能均有影响。研究结果表明,用安息香乙醚与二苯甲酮(质量比为2∶1)的混合体系作为光引发剂的引发效率最高,最佳涂料配方:环氧丙烯酸酯∶丙烯酸丁酯∶安息香乙醚∶二苯甲酮∶滑石粉为70∶20∶4∶2∶4(质量比)。     

陶瓷光固化3D打印技术研究进展及应用

与传统加工方法相比,光固化3D打印技术具有个性化、定制化、高分辨率等优点,可满足陶瓷精细结构的成型,在陶瓷材料加工方面展示出很大的潜力.这里首先介绍了光固化3D打印技术及常见的陶瓷材料,从陶瓷浆料制备、素坯热处理工艺方面进行讨论.同时对该技术在生物医学领域特别是在骨科、齿科中的应用进行总结.     

Ultraviolet‐curing behavior of an epoxy acrylate resin system

Ultraviolet (UV)‐curing behavior of an epoxy acrylate resin system comprising an epoxy acrylate oligomer, a reactive diluent, and a photoinitiator was investigated by Fourier transform infrared (FTIR) spectroscopy. The conversion changes of the resin system containing 20 phr of 1,6‐hexanediol diacrylate as a reactive diluent and 2‐hydroxy‐2‐methyl‐1‐phenyl‐propan‐1‐one as a photoinitiator were measured under different UV‐curing conditions. The fractional conversion was calculated from the area of the absorption peak for the vinyl group vibration occurring at 810 cm^?1. The effects of photoinitiator concentration, total UV dosage, one‐step or stepwise UV irradiation, UV intensity, atmosphere, and temperature on the curing behavior of the resin system were investigated. The conversion of the resin system increased rapidly at the initial stage of the UV‐curing process but increased very slowly after that. The final conversion of the resin system was mainly affected by total UV dosage. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1180–1185, 2005     

低温固化环氧阴极电泳涂料的制备

采用乙二醇单丁醚和甲乙酮肟对甲苯二异氰酸酯(TDI)进行全封闭,并将其加入到二乙醇胺改性的环氧树脂乳液中进行混合搅拌,制备了一种低温固化环氧阴极电泳涂料。研究了封闭反应温度、TDI用量和接枝反应温度对漆膜性能的影响,确定了适宜的工艺条件:甲乙酮肟封闭反应温度为40°C,接枝反应温度80°C,TDI质量分数为15%左右。在此条件下制备的漆膜可以在150°C/30min的条件下固化,所得漆膜厚度20μm,光泽70°,附着力1级,柔韧性1mm,铅笔硬度3H,冲击强度>50kg.cm,耐水性>800h,达到设计要求。     

Film performance and UV curing of epoxy acrylate resins

Radiation curing technology has encountered increased applications in recent years. The Asian geographical vicinity has and will be an expensive territory for years to succeed. There has been heightened governmental obligation to progress towards diminishing solvent practice to preserve the environment.

In the present study, the novolac as well as bisphenol-A based epoxy acrylates (or vinyl ester resins, VERs) were synthesised and extent of reaction and polymerisation was studied. It was observed that the above prepared oligomer when used with monofunctional/polyfunctional diluents can be cured in seconds time. Evaluation of film performance was also carried out.     

改性环氧树脂制备的热固性环氧沥青材料性能

采用改性环氧树脂和脂肪族多元羧酸固化剂（由C22：三元酸和二聚脂肪酸固化剂复配而成）及石油沥青制备了热固性环氧沥青材料。通过力学性能测试、DSC及扫描电镜研究了沥青含量对环氧沥青固化物拉伸性能、玻璃化温度、固化反应活性及相结构的影响。结果表明,沥青质量分数为44％的环氧沥青固化物的拉伸强度达8．37MPa,断裂伸长率达223．50％,玻璃化温度22．25℃,吸水率为0．2％。随着沥青含量的增加,沥青作为分散相的粒径越来越大,因而环氧沥青材料的拉伸强度降低。沥青含量的增加对固化物的玻璃化温度没有显著的影响。有沥青的环氧固化体系的反应活化能要小于无沥青的环氧固化体系。     

环氧有机硅油改性丙烯酸树脂的合成及性能

以偶氮二异丁腈为引发剂,通过丙烯酰氧基硅油与丙烯酸酯类单体的自由基共聚合反应,同时环氧828与丙烯酸共聚侧链羧基进行开环反应,合成以乙醇为主要溶剂的单相均匀牛顿型环氧有机硅油改性丙烯酸树脂。并对树脂涂膜的稳定性及硬度、耐水煮性,附着力等性能进行了研究。得到的树脂具有良好的热储稳定性,颜料广泛润湿性。环氧有机硅油改性丙烯酸树脂涂膜具有光泽高、硬度好、丰满度高、玻璃附着力强、耐水煮性好与透明性高等优异性能,适用于高档玻璃烤漆。     

减压条件下催化酯化合成聚乙二醇单甲醚丙烯酸酯

聚乙二醇单甲醚丙烯酸酯是合成梳形分散剂的重要单体。以聚乙二醇单甲醚和丙烯酸为原料,对甲苯磺酸为催化剂,减压条件下直接酯化合成聚乙二醇单甲醚丙烯酸酯,采用傅立叶红外光谱表征产物结构。对反应条件进行了优化,结果表明,在温度90 ℃、压力0.06 MPa、催化剂用量为反应物总质量的2.0%、阻聚剂用量为丙烯酸质量的1.5%、丙烯酸与聚乙二醇单甲醚物质的量比3∶1和反应时间5 h条件下,酯化率可达92.6%。高效液相色谱分析证明,用饱和食盐水和乙酸乙酯萃取后的产物纯度为99.2%。     

三维打印生物材料的发展现状

随着组织工程和再生医学不断进步,3D打印技术被用于开发和制造由仿生天然和合成材料组成的仿生支架。讨论3D打印"生物墨水"的进步和发展趋势,对3D打印多功能生物材料的发展具有积极意义。     

Toughened epoxy adhesive modified with acrylate based liquid rubber

The adhesive and mechanical properties of epoxy resins modified with carboxyl terminated poly(2‐ethylhexyl acrylate) (CTPEHA) liquid rubber have been investigated as a function of the concentration of liquid rubber. CTPEHA was synthesized by the bulk polymerization technique. CTPEHA oligomer was prereacted with the epoxy and the modified epoxy networks were made by curing with an ambient temperature curing agent. The modified epoxy networks were evaluated with respect to their adhesive and mechanical properties. The optimum properties were obtained at about 10–15 phr (phr stands for parts per hundred parts of epoxy resin) concentration of modifier. Fracture surface analysis by optical microscopy (OM) indicates the presence of two phase microstructures. © 2000 Society of Chemical Industry     

硅烷偶联剂改性环氧丙烯酸酯的合成与应用

针对环氧丙烯酸酯附着力和柔韧性差的缺点,通过在环氧丙烯酸酯中引入硅烷基团,合成硅烷改性的环氧丙烯酸酯。考察了各工艺参数对反应产品的影响,通过滴定和红外光谱分析跟踪反应进程和确定产物结构。合成产物通过和光固化单体、光引发剂混配成紫外光固化胶粘剂,并与改性之前的环氧丙烯酸酯作为主体树脂时的紫外光固化胶粘剂的性能进行了对比。研究发现,合成产物通过硅烷基团的引入,改善了环氧丙烯酸酯的柔韧性。同时,由于硅烷偶联剂基团在固化过程中水解露出的硅羟基增强了对无机底材的附着力,使得紫外光固化胶粘剂的综合性能得到了优化和改善。     

3D printing of high-purity silicon carbide

A method for advanced manufacturing of silicon carbide offering complete freedom in geometric complexity in the three-dimensional space is described. The method combines binder jet printing and chemical vapor infiltration in a process capable of yielding a high-purity, fully crystalline ceramic—attributes essential for ideal performance in very high-temperature applications or in the presence of displacement damage. Thermal conductivity and characteristic equibiaxial flexural strength of the resulting monolithic SiC at room temperature are 37 W·(m·K)⁻¹ and 297 MPa, respectively.     

KH560改性双组分室温固化环氧结构胶的制备与性能

将γ-缩水甘油醚氧丙基三甲氧基硅烷(KH560)与环氧树脂(EP)预反应,采用黏度计、万能电子材料试验机、红外光谱、差示扫描量热仪,考查了KH560含量对EP/改性聚酰胺室温固化环氧结构胶性能的影响。结果表明,KH560含量从0增加至9质量份(每100份EP中加入量)时,胶体拉伸强度从51 MPa降低至36.5 MPa;压缩强度从79.7 MPa降低至53 MPa;粘接强度从8.7 MPa增至11.7 MPa。同时,固化物的热稳定性也有一定程度提高,未改性及9份KH560改性的EP固化物50%热失重的温度分别为382.1℃与403.6℃。