低黏度高分子质量超支化环氧树脂的合成及性能

利用一步法合成了低黏度高分子量的第四代芳香族超支化环氧树脂HTDE-4,该种树脂能作为环氧树脂的稀释剂。将HTDE-4与双酚A型环氧树脂杂化复合,研究其固化物的机械性能。杂化树脂的性能随超支化环氧树脂含量的增加先增加后下降;当用量为12%(质量分数)左右时,体系的拉伸强度、弯曲强度、冲击强度和断裂韧性分别提高15.6%,14.8%,158.9%和36.9%,断裂韧性达到2.78 kPa.m1/2。用傅里叶变换红外光谱和核磁共振氢谱、扫描电镜和分子模拟技术对产物进行了研究。     

增强增韧环氧杂化树脂制备与性能研究

双酚A型环氧树脂的增韧增强研究是热固性树脂的重要发展方向之一,利用一步法合成了脂肪族端羟基超支化聚合物(HTP-2),再利用"嫁接法"制备了液体型超支化环氧树脂HTPE-2,研究了HTPE-2/双酚A型环氧杂化树脂的力学性能和热学性能.利用红外光谱、扫描电镜、热分析和分子模拟技术讨论了超支化环氧树脂的结构、杂化树脂的性能和原位增韧增强机理.结果显示,杂化树脂的力学性能随超支化环氧树脂含量的增加先提高后下降,具有最大值;当HTPE-2的质量分数为9%～12%时,杂化树脂的拉伸强度、弯曲强度、冲击强度和断裂韧性分别提高18.0%、35.7%、192.4%和39.6%,综合性能较好,但玻璃化转变温度(T8)和热分解温度有所下降.     

超支化环氧树脂的分子模拟及其杂化树脂的性能

利用一步法合成了4种不同分子质量的低黏度液态超支化环氧树脂,并利用该树脂与双酚A型环氧树脂(E-51)杂化复合,研究其固化物的冲击性能.杂化树脂的冲击性能随超支化环氧树脂含量和/或分子质量的增加先增加后下降,具有最大值;当相对分子质量在3 400左右、质量分数为12%左右时,体系的冲击强度达到最大值,与纯E-5l相比提高了208.8%.利用FT-IR和分子模拟技术对超支化环氧树脂的性质和结构进行了表征,采用sEM对杂化树脂的断裂表面进行表征.并解释了增韧机理.     

新型脂肪族超支化环氧树脂的制备及其改性作用

采用一步法合成了新型脂肪族超支化环氧树脂HTPE-3,利用FT-IR对其结构进行了表征。研究了双酚A型环氧树脂E-51/HTPE-3杂化树脂的力学性能和热性能。结果显示,杂化树脂的韧性和强度随HTPE-3含量的增加先增加后降低,具有极大值;当HTPE-3质量分数为12%左右时,与纯E-51树脂相比,杂化树脂的冲击强度和断裂韧性分别提高了169.8%和35.2%,拉伸强度和弯曲强度分别提高了6.5%,10.0%,维卡软化点温度、玻璃化转变温度和热分解温度略有下降。     

UV固化超支化PUA/SiO_2杂化涂料的制备及性能研究

以TEOS(正硅酸乙酯)为无机前驱体、KH-570(γ-甲基丙烯酰氧丙基三甲氧基硅烷)为改性剂,采用溶胶凝胶法在酸性催化条件下合成了改性硅溶胶;然后以HPUA[超支化PUA(聚氨酯丙烯酸酯)]为低聚物、PETA(季戊四醇三丙烯酸酯)为活性稀释剂,制备了UV(紫外光)固化HPUA/SiO_2杂化涂料。研究结果表明:杂化涂膜的热稳定性高于纯PUA涂膜;当w(改性硅溶胶)=16%(相对于单体总质量而言)时,杂化涂料的综合性能相对最好,其柔韧性为2 mm、铅笔硬度为4H和附着力为1级,并且涂膜的耐溶剂性、耐腐蚀性和耐磨性俱佳。     

溶胶-凝胶法制备环氧树脂／SiO2杂化材料的研究

以环氧树脂、正硅酸乙酯（TEOS）、У-氨丙基三乙氧基硅烷（KH-550）为原料，采用溶胶-凝胶（Sol-Gel）法制备了环氧树脂／SiO2杂化材料。研究了TEOS用量、KH-550用量、温度对环氧树脂/SiO2杂化材料性能的影响。利用透射电镜（TEM）研究了SiO2在杂化材料中的分散状态，利用扫描电镜（SEM）对杂化材料的拉伸断口的微观形貌进行了研究，并用差示扫描量热（DSC）法研究了杂化材料的耐热性能。结果表明，TEOS含量在3％，KH-550含量在2％、反应温度在60℃时，杂化材料的拉伸强度、断裂伸长率、冲击强度和弯曲强度分别提高了30.1％、53.9％、34.4％、12.5％；生成的SiO2颗粒的平均尺寸为20nm左右；杂化材料玻璃化温度比纯环氧树脂提高20℃以上。     

超支化聚合物改性环氧树脂的研究

超支化聚合物是一类很有前景的热固性树脂改性材料.以三羟甲基丙烷(TMP)和二羟甲基丙酸(DMPA)为反应单体,采用一步法合成了超支化聚合物,研究了超支化聚合物用量对双酚A环氧树脂的力学性能影响,并利用差示扫描量热分析(DSC)、热失重分析(TGA)研究了固化物的热性能.结果表明,加入15%的超支化聚合物后,环氧树脂的冲击强度和弯曲强度分别提高了153%,19.3%,环氧树脂的耐热性能也有一定程度的提高.表明该超支化聚合物是一类潜在的环氧树脂改性剂.     

超支化聚酯接枝超细二氧化硅改性环氧树脂研究

在催化剂存在下,二羟甲基丙酸(DMPA)为反应单体,可成功地接枝超支化聚酯到经硅烷偶联剂γ-氨丙基三乙氧基硅烷(KH-550)处理过的超细二氧化硅表面。通过IR、TG、氨基分析、亲水性测试等表征其性能。结果表明,每1.5 g二氧化硅和0.65 g KH-550反应表面氨基含量最多,为7.986 mmol/g;每1.00 g KH-550改性二氧化硅和3.00 g DMPA反应产物接枝率最高,为85.55%,产物亲油疏水性最好,使液体石蜡黏度改变最小。不同代超支化聚酯改性二氧化硅固化环氧树脂,漆膜性能表明,4.00 g DMPA改性二氧化硅固化环氧树脂漆膜铅笔硬度和柔韧性增加,改性效果最优。     

脂环族环氧树脂／双酚A环氧树脂共混改性研究

采用脂环族环氧树脂（EPL-4221）与双酚A型环氧树脂E-51共混,用酸酐固化剂和促进剂使其固化,研究脂环族环氧树脂的用量对共混树脂性能的影响及其规律性,包括冲击强度、弯曲强度、拉伸强度、维卡软化点温度、漆膜的粘附力、铅笔硬度、耐磨性以及拉伸剪切强度。结果表明,随脂环族环氧树脂用量的增加,共混树脂的综合性能先增加后降低,脂环族环氧树脂的质量分数为15％-20％时,具有最大值。     

蓖麻油基超支化环氧树脂的合成及其增韧应用

采用异佛尔酮二异氰酸酯(IPDI)和环氧丙醇反应得到的含—NCO基团的半加成物(IG)与蓖麻油基超支化聚酯多元醇(C10)反应得到蓖麻油基超支化环氧树脂(C10-IG)。通过红外光谱、核磁共振光谱及力学性能测试研究了C10-IG的结构及其添加量对E-51环氧复合材料性能的影响。结果表明,复合材料的力学强度随着C10-IG用量的增加,先增大后减小。当C10-IG的添加质量分数为6%时,材料的综合性能最佳,拉伸强度、弯曲强度、剪切强度和冲击强度较纯树脂体系分别提高了11.1%,8.5%,20.1%和133.9%。通过冲击断裂面形貌分析认为C10-IG对E-51树脂体系的增韧机理为原位增韧。     

Bisphenol-A epoxy resin reinforced and toughened by hyperbranched epoxy resin

The study on toughening and reinforcing of bisphenol-A epoxy resin is one of important developmental direction in the field. This paper reports a one-pot synthesis of aromatic polyester hyperbranched epoxy resin HTDE-2, an effect of HTDE-2 content on the mechanical and thermal performance of the bisphenol-A (E51)/HTDE-2 hybrid resin in detail. Fourier transform infrared (FT-IR) spectrometer, scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical thermal analysis (DMA) and molecular simulation technology are used to study the structure of HTDE-2, performance and toughening and reinforcing mechanism of the HTDE-2/E51 hybrid resin. It has been shown that the content of HTDE-2 has an important effect on the performance of the hybrid resin, and the performance of the HTDE-2/E51 blends has maximum with the increase in HTDE-2 content. The impact strength and fracture toughness of the hybrid resin with 9 wt-% HTDE-2 are almost 3.088 and 1.749 times of E51 performance respectively, furthermore, the tensile and flexural strength can also be enhanced about 20.7% and 14.2%, respectively. The glass transition temperature and thermal degradation temperature, however, are found to decrease to some extent. __________ Translated from Journal of South China University of Technology (Natural Science Edition), 2006: 34(9): 90–94 [译自: 华南理工大学学报 (自然科学版)]     

Toughness and reinforcement of diglycidyl ether of bisphenol-A by hyperbranched poly(trimellitic anhydride-butanediol glycol) ester epoxy resin

Hyperbranched epoxy resin shows best comprehensive performance in epoxy resin system and is considered as a kind of toughness and reinforcement additive. This article reports on the use of novel hyperbranched poly(trimellitic anhydride-butanediol glycol) ester epoxy resin (HTBE) prepared by us as a functional additive to an epoxy amine resin system. The effect of molecular weight and content of the HTBE on the performance of the diglycidyl ether of bisphenol-A (DGEBA)/HTBE hybrid resin are discussed in detail, and their performance has maximum with the increase of content and molecular weight of HTBE. The impact strength and fracture toughness of the hybrid resin containing 9 wt% second generation of HTBE are 48.2 kJ/m² and 2.71 MPa m^1/2, and which almost are 2.77 and 1.5 times of DGEBA performance respectively. Furthermore, the tensile and flexural strength can also be enhanced about 17%. The fracture surface micrograph of hybrid resin shows no microphase separation of the HTBE/DGEBA blends that facilitates an enhanced interaction to achieve excellent toughness and strength enhancement of the cured systems by scanning electron microscope (SEM). A novel situ reinforcing and toughening mechanism and model are discovered and confirmed by SEM, molecular simulation, and dynamic mechanical thermal analysis technology. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers     

端羧基超支化聚酯改性环氧树脂固化体系研究

利用丁二酸酐对端羟基超支化聚酯(AHBP)的端基进行改性,得到新的端羧基超支化聚酯(CHBP),并将其用于环氧树脂体系的增韧。研究了CHBP用量、羧基含量对环氧树脂/甲基四氢苯酐(EP/MeTHPA)固化体系的力学性能和热性能的影响。结果表明,改性后分子末端全部带羧基的CHBP的增韧作用最好,冲击强度可达18.5kJ/m2。CHBP质量分数为15%时,固化物的冲击强度可达18.2 kJ/m2,拉伸强度64.86 MPa,玻璃化温度(Tg)从100℃提高到106℃左右,可满足增韧环氧树脂的同时不降低其耐热性的要求。     

Modification of hyperbranched epoxy by vegetable oil-based highly branched polyester resin

Modification of existing polymers by physico-chemical technique is not only interesting and useful to the academic community but the resulted product is attractive to industrial application too. In this investigation, hyperbranched epoxy was modified by vegetable oil-based highly branched polyester resin at different weight percentages and properties of the cured systems were evaluated in order to justify them as advanced thin film materials with high adhesive strength. Modified systems were studied using FTIR, XRD, TGA and SEM analyses. Curing reaction was confirmed by FTIR study and swelling test. Performance characteristics like tensile strength, impact strength, adhesive strength, flexibility, scratch hardness, gloss and chemical resistance of cured films have also been studied. Modified systems showed improved properties over pristine epoxy. Comparison study of modified systems showed that hyperbranched epoxy with 30 wt% polyester content is the best composition w.r.t performance and might be utilized in advanced thin film application.     

聚氨酯改性环氧树脂胶粘剂的制备及性能研究

由端-NCO基聚氨酯(PU)预聚物与环氧树脂反应,制备了PU接枝改性环氧树脂。着重探讨了PU预聚物的含量、活性稀释剂的含量和异氰酸酯结构等因素,对改性环氧树脂的粘度和粘接性能的影响。实验结果表明,该改性环氧树脂的粘度随着PU预聚物含量的增加而逐渐增大,随着活性稀释剂含量的增加而逐渐降低,而且在相同的条件下,用不同的二异氰酸酯改性环氧树脂的粘度大小次序为:IPDI型>MDI型>TDI型;该改性环氧树脂在PU预聚物含量为20%时,对铝片/铝片的剪切强度最大(7.82 MPa);在PU预聚物含量为10%时,对铁片/铁片的剪切强度最大(11.70 MPa),而且TDI型和IPDI型改性环氧树脂的粘接性能明显好于MDI型改性环氧树脂。     

A novel hybrid linear–hyperbranched poly(butylene adipate) copolymer as an epoxy resin modifier with toughening effect

A study was carried out on the effect of a hybrid linear–hyperbranched poly(butylene adipate) copolymer on the properties of a commercial epoxy resin. First, the synthesis of the hyperbranched systems was optimized. These systems were obtained by reacting linear oligomers with 1,1,1‐tris(hydroxymethyl)propane used as branching agent and varying the reaction times from 16 to 44 h. The synthesized samples were characterized through matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry, differential scanning calorimetry and thermogravimetric analysis. Results showed that for reaction times of 30 h a highly branched system, namely 5HB30, was obtained. This system was chosen as toughening agent for a commercial high‐performance epoxy resin. A kinetics analysis of epoxy/5HB30 blends indicated that the hyperbranched system had no accelerator or catalytic effect on the crosslinking reaction in the resin. Furthermore, it was demonstrated that 5HB30 acted as an excellent toughening agent, increasing significantly impact resistance up to 90% with respect to neat epoxy resin. The toughness behaviours of epoxy‐based blends were explained by investigating the fracture surface after impact tests through scanning electron microscopy before and after solvent etching. It was observed that the globular‐like hyperbranch‐rich domains, dispersed throughout the continuous epoxy resin, were able to absorb the impact energy without affecting thermal stability. © 2015 Society of Chemical Industry     

氯甲基笼型倍半硅氧烷改性双酚A环氧树脂性能

引言双酚A环氧树脂是目前应用最广、用量最大的环氧树脂,具有良好的化学稳定性、电气绝缘性被广泛应用于涂料和电子电器等领域;然而,双酚A环氧树脂存在耐热性较差和固化后脆性大等缺点,因此如何提高环氧树脂的耐热性及力学性能等是目前改性研究的热点之一[1-5]。而笼型多面体倍半硅氧烷(POSS)是一类具有(RSiO1.5)n通式的纳米材料,因其特殊的分子组成结构使得POSS具     

Effect of hyperbranched epoxy resin on mechanical properties of short carbon fiber‐reinforced epoxy composites

Short carbon fiber‐reinforced composites (SCFRCs) have attracted increasing attention owing to their comprehensive performance and easy processing route. However, the imperfect interfacial adhesion and serious stress concentration at the fiber/matrix interface have hampered their engineering application. In this article, we first report the preparation of SCFRC modified by a low‐viscosity liquid hyperbranched epoxy resin (Hyper E102). We then investigated the effect of Hyper E102 content on thermal and mechanical properties. The results show that the overall performance of the SCFRC first increases and then decreases with the increasing content of Hyper E102. With the incorporation of 12 phr Hyper E102, the tensile strength, fracture toughness, notched, and unnotched impact strength of SCFRC were increased by 16.7, 74.9, 95.3, and 194.5%, respectively. The toughening and reinforcing mechanisms were attributed to the following three aspects. First, the Hyper E102 improves the impregnation property of epoxy matrix against fibers, which helps form a better interfacial adhesion. Second, the incorporation of Hyper E102 reduces the internal stress level and stress concentration of the SCFRC. Finally, the critical crack length inside the SCFRC can be remarkably increased with the incorporation of Hyper E102, which can enhance the damage tolerance of a composite. POLYM. COMPOS., 37:2727–2733, 2016. © 2015 Society of Plastics Engineers     

松香基超支化环氧树脂的合成及性能研究

首先以马来海松酸三缩水甘油酯(MPTGE)和马来海松酸(MPA)为主要原料,一步法合成松香基超支化聚酯(HPR),然后HPR再与环氧氯丙烷(ECH)经开环酯化、闭环反应,得到松香基超支化环氧树脂(HPER)。讨论了开环酯化、闭环反应中各因素对产物性能的影响,采用凝胶色谱仪、红外光谱仪对合成产物进行了表征,并确定了适宜的工艺条件:氯丙烷(ECH)与超支化聚酯(HPR)物质的量比为18∶1,开环反应以四丁基溴化铵为催化剂,用量为反应物总质量的2%,反应温度100℃;闭环反应中以氢氧化钠溶液作为中和剂,50℃下反应3 h。所得环氧树脂的环氧值为0.23 mol/100 g,粘度为850 mPa.s。