桐油改性酚醛树脂及其在刹车片中的应用研究

将苯酚和桐油在酸性条件下反应,然后在碱性条件下与甲醛反应制得桐油改性酚醛树脂。利用红外光谱、差示扫描量热法对桐油改性酚醛树脂的结构和固化过程进行研究,并测试其剪切强度、冲击强度和硬度等力学性能。结果表明,桐油改性酚醛树脂的剪切强度、冲击强度较未改性树脂大,硬度适中。将桐油改性酚醛树脂制成刹车片,测试其摩擦磨损性能。结果表明,刹车片的摩擦系数大、摩擦性能稳定、磨损率低。     

改性酚醛树脂的合成及应用研究

本文介绍用腰果壳油与苯酚、甲醛反应，在复合催化剂存在下，用一步法制得改性酚醛树脂。该树脂具有热分解温度高，韧性好等特性，用此树脂与蛭石等材料复合制成的摩擦材料，具有耐温、耐磨、冲击性能好等特性，是有机基摩擦材料较理想的粘结剂。     

溴化环氧树脂交联桐油改性酚醛树脂用于覆铜箔板的研究

介绍了国内首次采用桐油改性酚醛树脂与溴化环氧树脂混合热压交联制玻璃布基覆铜箔板，测试了所制覆铜箔板有关的电性能，结果表明：制品性能指标达到或超过了国内类似环氧改性酚醛树脂覆铜箔板产品的性能。     

桐油改性酚醛树脂及其在刹车片中的应用研究

本文用桐油改性酚醛树脂，利用红外光谱、差示扫描量热法分析技术对改性树脂的结构和固化过程进行了研究，测试了改性树脂的剪切强度、冲击强度和硬度等力学性能。并将改性树脂制成刹车片，测试了其摩擦磨损性能，结果表明，刹车片的摩擦系数大、磨损率低。     

高性能改性酚醛树脂胶粘剂的研究

利用钼改性酚醛树脂，对改性后树脂的综合性能进行正交分析，确定最佳工艺条件为：以盐酸为催化剂，用量为苯酚质量的0．5％，反应温度为90℃，反应时间3．5h。并对钼酚醛树脂进行了TG分析，改性后树脂固化温度在160℃左右，热分解温度为531．8℃，600℃下的热失重率为17．5％，可知钼酚醛树脂的热分解温度和耐热性比普通酚醛树脂要高。     

高强度酚醛层压布板的制备与性能研究

制备了高强度酚醛层压布板,并研究了其性能。讨论了桐油改性酚醛树脂和针状硅灰石粉对酚醛层压布板冲击强度和弯曲强度的影响,并对桐油改性酚醛树脂进行了耐热性能分析。研究结果表明,将甲阶酚醛树脂和桐油改性酚醛树脂共混,随着共混树脂中桐油改性酚醛树脂比例的增加,以此为基体树脂制得的酚醛层压布板的冲击强度在横、纵两个方向上均有大幅度提高。与未添加针状硅灰石粉相比,添加针状硅灰石粉酚醛层压布板的冲击和弯曲强度均有提高,横、纵向冲击强度分别提高23.3%,9.1%,弯曲强度分别提高0.4%,5.4%。针状硅灰石粉经偶联活化改性后,与未偶联活化改性针状硅灰石粉相比,添加改性针状硅灰石粉酚醛层压布板的冲击和弯曲强度进一步得到提高,横、纵向冲击强度分别提高3.9%,15.0%,弯曲强度分别提高4.1%,4.0%。350℃之前,桐油改性酚醛树脂能保持比较好的热稳定性;在大于350℃的高温区,桐油改性酚醛树脂较甲阶酚醛树脂的热稳定性下降明显。     

高性能刹车片专用耐高温低膨胀酚醛树脂合成

为了提高作为刹车片黏结剂主要成分的酚醛树脂的耐高温低膨胀性能,本文研究了苯乙炔酚醛树脂(PEPF)树脂,它是由苯酚和3-苯乙炔苯酚的混合物与甲醛在酸性催化剂条件下合成;它是一种改性酚醛树脂,其摩擦性能和耐高温性能较一般的改性树脂高。     

不同种类酚醛树脂黏结剂对摩擦材料性能的影响

分别以未改性通用酚醛树脂、特殊改性刹车片专用酚醛树脂、腰果壳油改性酚醛树脂、丁腈橡胶改性酚醛树脂为黏结剂,玄武岩纤维、钢纤维为增强纤维制备四种酚醛树脂基摩擦材料。对试样进行物理性能、机械性能和摩擦磨损性能测试。结果表明,四种摩擦材料的密度相差不大,未改性通用酚醛树脂基摩擦材料的硬度符合刹车片使用要求,腰果壳油改性酚醛树脂基摩擦材料具有最佳的冲击强度和压缩强度;在摩擦过程中,腰果壳油改性树脂摩擦表面形成碳化膜,碳化膜的存在使摩擦材料的摩擦系数相对比较稳定,降低了磨耗量。研究表明,腰果壳油改性树脂基摩擦材料的综合性能最优。     

国内纸基覆铜箔板用热固性酚醛树脂的发展

本文对热固性酚醛树脂在我国纸基覆铜箔板制造中的应用作一综述。并对桐油改性酚醛树脂在此领域中的技术发展作一探讨。     

光敏酚醛环氧丙烯酸酯的合成工艺

本文以丙烯酸和F-44环氧树脂为原料，合成了一种既含有环氧基又含有丙烯酸基的光敏酚醛环氧丙烯酸酯树脂。研究了催化剂种类、催化剂用量、反应时间、反应温度对丙烯酸转化率的影响。结果发现，以三乙胺作催化剂，反应温度为95℃，催化剂用量为树脂质量的2％，酯化反应在6h之内完成所合成的树脂制成的涂膜具有优良的力学性能、耐溶剂性能和耐酸碱性能。用FT—IR对所合成树脂的结构进行了表征。     

桐油改性双环戊二烯不饱和树脂的合成研究

利用缩聚反应后期桐油与双环戊二烯不饱和聚酯(DCPD-UPR)主链上不饱和双键的Diels-Alder(D-A)反应合成了桐油改性DCPD-UPR,研究了各种原料用量对桐油改性DCPD-UPR其浇注体力学性能的影响。结果表明:当顺酐与苯酐的物质的量比为2∶1～3∶1,双环戊二烯与顺酐物质的量比为0.6～0.8∶1,1,2-丙二醇与二甘醇物质的量比2∶1,缩聚反应后期加入10%(质量分数)桐油,苯乙烯质量分数为35%～40%时,获得的桐油改性DCPD-UPR粘度适中,浇注体的断裂伸长率提高了78.2%,冲击强度提高了82.0%。     

硼酸-桐油双改性酚醛树脂的表征及反应机理研究

文章利用实验及IR图谱分析的方法,对硼酸-桐油双改性酚醛树脂的结构进行了表征,并对其反应机理进行了分析。结果表明,改性后树脂分子中生成高键能的B-O键及含硼的三向交联结构,可使树脂达到耐热性提高的目的;引入了桐油柔性链,桐油分子中部分双键打开,连接于苯环的邻位或对位处,从而使得刚性的硼酚醛树脂分子链段中嵌有柔性的烷基长链,形成网状结构,起到内增韧作用,使树脂的柔韧性得到改善。     

邻苯二酚-桐油树脂的成膜性能研究

以桐油和邻苯二酚为原料合成邻苯二酚-桐油树脂，对合成树脂进行红外光谱结构分析，并考察了树脂在常温、加热及催干剂条件下的成膜性能。结果表明，邻苯二酚-桐油树脂具有天然生漆漆酚类似的特征功能基结构和性能，难以自干成膜，但可受热固化或在催干剂作用下聚合固化干燥成膜；由催化剂催化固化得到的邻苯二酚-桐油树脂涂膜外观色泽好，具有较好的硬度、附着力、耐冲击性，以及优良的热稳定性和耐化学介质性能。     

桐油预酯化反应研究

采用强酸阳离子交换树脂为催化剂,进行了桐油和甲醇的预酯化反应的研究。反应在固定床反应装置上进行,考察了反应温度、反应压力、醇油摩尔比和体积空速对反应的影响,得到最适宜的反应条件为:反应温度75℃,反应压力1.5 MPa,醇油摩尔比10:1,体积空速1 h~(-1)。在此反应条件下,反应酯化率为94.5%,反应产物酸值由5.5 mg(KOH)·g~(-1)降为0.3 mg(KOH)·g~)-1)0。     

桐油改性曼尼期碱固化剂的合成及性能研究

桐油的共轭双键具有极强的反应活性,易与苯酚芳环上邻或对位的活性氢发生傅氏取代反 应。余下的两个活性氢位置仍然能与胺类、醛类发生曼尼期碱的缩合反应。本文研究了桐油改性 曼尼期碱的合成反应的条件、影响因素及产品的固化性能,并指出桐油改性曼尼期减为一综合性 能优异的环氧树脂固化剂。     

Preparation and properties of epoxy‐modified tung oil waterborne insulation varnish

This work aimed to develop a novel epoxy‐modified tung oil waterborne insulation varnish with blocked hexamethylene diisocyanate as a curing agent. The Diels–Alder reaction between tung oil and maleic anhydride, and the ring‐opening esterification reaction of epoxy resin were confirmed. The conversion rate of epoxy was explored as a function of reaction time and temperature. The effects of epoxy resin content on the thermal stability, water absorption and insulation properties (insulation strength, volume resistivity, and surface resistivity) of films were investigated, and the resistances of films to salted water were evaluated. The increase in epoxy resin contents could improve the thermal stability and insulation properties of films, and decreased the water adsorption of films, but when the epoxy resin content reached 30% and above, the water solubility of resin became poor. After being immersed in 3.5 wt % NaCl solution, the electrical insulation strength of films were lower than that in dry state, and decreased as the immersed time prolonged. In particular, the electrical insulation strength loss of films increased significantly for epoxy resin content at 15% and below. Furthermore, the increase of epoxy resin content could improve the hardness and adhesion of films, but the flexibility of films became worse. On the basis of experimental, the epoxy resin content at 25% was appropriate to prepare waterborne epoxy‐modified tung oil resin. The resulting varnish may have potential as an immersing insulation varnish for the spindle of electric motor. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42755.     

改性醇酸树脂的合成

以桐油、豆油、三羟甲基丙烷、苯酐、己二酸为原料合成基础醇酸树脂 ,再用苯乙烯、丙烯酸酯进行接枝共聚就制得改性醇酸树脂。在制造醇酸树脂过程中添加适量的抗氧剂 ,就可以防止胶化。制得的产品是均匀透明的 ,可用于制造浅色的不泛黄的涂料     

摩擦材料用改性酚醛树脂的研究进展

综述了摩擦材料用改性酚醛树脂(PF)的研究进展,其中分别对钼、硼无机物改性PF和聚酰胺、腰果壳油、桐油、亚麻油、橡胶等有机物改性PF进行了讨论,并对纳米PF树脂和复合改性PF进行了介绍。改性PF的性能得到了显著改善,用其作基体制备的摩擦材料具有摩擦系数稳定、磨损率低等优点。     

Eucalyptus bark lignin substituted phenol formaldehyde adhesives: A study on optimization of reaction parameters and characterization

The major adhesive resin worldwide used in the manufacture of plywood is phenol formaldehyde resole (PF) resin. The raw material for this kind of adhesive is derived from petroleum oil. Because of rising prices of crude oil and the scarcity of petroleum products, their replacement by natural resource–based raw material has become a necessity. In the present work, the possibility of replacing phenol in PF resin with lignin was explored. The parameters for preparation of bark lignin substituted PF (LPF) adhesive, such as lignin concentration, formaldehyde to phenol molar ratio, catalyst concentration, reaction time, and reaction temperature, were optimized. It was found that up to 50 wt % of phenol can be substituted by lignin to give an LPF adhesive with better bonding strength compared to that of control PF resin. Prepared resins were characterized using IR, DSC, and TGA. IR spectra of LPF adhesive showed structural similarity with that of PF adhesives. Thermal stability of LPF adhesive was found to be lower compared to that of control PF (CPF) adhesive. DSC studies revealed a lower curing temperature for LPF resin than that for CPF resin. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3514–3523, 2004     

Determination of true iodine number of oils with conjugate unsaturation by use of hypochlorous acid reagent

Summary Hypochlorous acid reagent has conveniently been used for the determination of total unsaturation in oils containing conjugated double bonds. The use of 0.1 N HOCl reagent normally employed for oils with isolated double bonds leads to incomplete absorption, and the increase in concentration and reaction period gives desirable results in the presence of mercuric acetate catalyst. A 1-hr. reaction period with 0.3 N HOCl reagent in the presence of 2.5% solution of the catalyst is recommended. A sample size varying between 0.07–0.1 g. and a 300–400% excess reagent should be employed to obtain reliable results. This procedure can be effectively used for determining the total unsaturation of tung oil, isomerized fatty acids, and dehydrated castor oil and can be employed for detecting the adulteration in commercial samples of tung oil, which cannot be ordinarily detected by the determination of the partial iodine number with the help of conventional procedures.