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1.
目的合成丙烯酸改性邻甲酚醛环氧树脂。方法研究反应温度、催化剂种类和反应时间对丙烯酸转化率的影响。结果在烯丙基/环氧基的摩尔比为0.30:1时,温度控制在95℃,采用N,N-二甲基苯胺作为催化剂(用量为反应物的1.00%),反应3h后,丙烯酸转化率可达到98.80%。结论控制适当的反应条件,丙烯酸可以达到较高水平的转化率。  相似文献   

2.
将纳米SiO2加入到环氧丙烯酸酯体系中,配制成紫外光固化涂料;对涂料涂膜的抗冲击强度、附着力、柔韧性、硬度、耐老化性能进行了测试,并对涂膜进行了热重分析.研究表明,涂料性能随着纳米SiO2用量的增加而提高,但当纳米SiO2的用量占总物质质量分数的5%时,再增加纳米SiO2的用量,涂料的某些性能反而下降;纳米SiO2较佳的加量为涂料质量分数的3%~5%,在此范围内,所制得的环氧丙烯酸酯紫外光固化涂料涂膜的硬度达3H,抗冲击强度达4.9N·m、附着力达1级、柔韧性达1mm.光泽度85%~90%、鲜映性8~9级、耐人工老化800h失光率18.7%~23.4%.  相似文献   

3.
水性双组分丙烯酸酯聚氨酯涂料   总被引:5,自引:0,他引:5  
用内乳化剂二羟甲基丙酸(DM PA)对异氰酸酯进行改性,然后将其与丙烯酸酯多元醇反应制备了水性双组分丙烯酸酯聚氨酯涂料。研究了反应物摩尔比n(-NCO)/n(-OH)、中和度等因素对涂膜性能和外观的影响。结果表明:经DM PA改性后,增加了异氰酸酯预聚物的亲水性及其与丙烯酸酯多元醇的相容性;涂膜的拉伸强度和耐水性均有较大的提高,涂膜的外观也有所改善。  相似文献   

4.
有机硅氧烷改性水性羟基丙烯酸树脂的研制   总被引:9,自引:1,他引:8  
在水性羟基丙烯酸树脂的合成中引入有机硅氧烷单体进行改性,以提高水性双组分丙烯酸聚氨酯木器涂料的耐水、耐溶剂等涂膜性能.探讨了树脂配方中丙烯酸酯类单体、有机硅氧烷单体的种类以及树脂酸值、羟基含量、玻璃化温度、中和度等参数对涂料双组分相容性、干燥性能和涂膜性能的影响、研究表明,在合成配方中选择较高活性的丙烯酸羟乙酯单体和阻碍性的乙烯基三异丙氧基硅烷单体,选择酸值在35~50mg/g(以KOH含量计)之间、羟基含量在3.5%左右、玻璃化温度在25℃左右并配合60%左右的中和度,所合成的树脂配制成的木器涂料具有优异的耐水和耐溶剂性,其干燥及胶化时间均达施工要求.  相似文献   

5.
紫外光固化环氧大豆油树脂的合成和表征   总被引:2,自引:0,他引:2  
研究了可作为紫外光固化涂料和油墨等产品的基体树脂的改性环氧大豆油树脂的合成及表征.利用环氧大豆油的环氧环的化学活性,先后与丙烯酸和马来酸酐进行反应,分别合成了油溶性环氧大豆油丙烯酸酯(AESO)和水溶性的马来酸改性环氧大豆油树脂(MAESO).并用红外和核磁对两种产物的结构进行了表征.添加紫外光引发剂后,两种产物在紫外光照射下均可快速固化.合成AESO最佳条件为环氧大豆油:丙烯酸=1.2:1(摩尔比),催化剂三苯基膦的用量为总质量的1%,反应温度为120℃;合成MAESO最佳条件为AESO:马来酸酐=4:1(摩尔比),催化剂钛酸正丁酯用量为1%,反应温度90℃.  相似文献   

6.
用于紫外光固化涂料的羧基化环氧丙烯酸酯水分散性研究   总被引:8,自引:0,他引:8  
根据亲水亲油平衡值(HLB)设计了以马来酸酐改性环氧丙烯酸酯的方案,合成了具有良好水分散性的羧基化环氧丙烯酸酯树脂.用电导率法表征了羧基化环氧丙烯酸酯的水分散性,研究了羧基化程度、中和程度对树脂水分散性的影响;配制了水性紫外光固化涂料,所得涂膜性能良好.  相似文献   

7.
以苯乙烯(St)、甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)、丙烯酸-2-乙基己酯(EHA)为基本单体,分别以丙烯酸(AA)、丙烯酰胺(AM)、N-羟甲基丙烯酰胺(NAM)、丙烯酸-2-羟乙酯(HEA)为功能性单体,采用半连续的乳液聚合工艺,合成了丙烯酸酯类的多元共聚物乳液。通过对所得乳液表面能和黏度的变化分析,筛选出低表面能低黏度的功能性单体,最优用量为w(AA)1%~2%,w(AM)05%~1%,w(NAM)为0.5%以下,HEA的引入使乳液体系的表面能增加,尽量不用或少用。优化后的乳液,加入少量的成膜助剂,可以很好地铺展在电晕后的BOPP塑料薄膜表面,干燥后涂膜与基材的耐揉搓性、耐水性等性能优异,剥离强度可以达到500N/m。  相似文献   

8.
合成了一种含生色团的环氧单体,将它与酚醛缩水甘油醚和双环氧丙烯酸酯及光引发剂溶解在一起后涂膜,用UV光照固化,同时在高压电场下极化,得到了一种极化互穿聚合物网络.该体系二阶非线性光学系数d33值为9.4×10-8esu,d33热稳定性良好.  相似文献   

9.
以4,4'-二羟基二苯硫醚(TDP)和环氧氯丙烷为原料,合成出了一种含硫的环氧树酯,然后采用丙烯酸酯化,制备能够紫外光固化快速成型用的环氧丙烯酸酯预聚物。通过研究反应时间、反应温度、催化剂类型及用量对反应及产物性能的影响,得到了合成环氧丙烯酸树酯的较佳工艺条件。并用傅里叶变换红外光谱、核磁共振氢谱对环氧树酯以及环氧丙烯酸树酯结构进行了表征。  相似文献   

10.
以甲苯-2,4-二异氰酸酯、SAN树脂、丙烯酸羟乙酯等原料合成聚氨酯丙烯酸酯预聚物,研究了反应温度、反应时间及催化剂浓度对树脂合成的影响.得出合成该预聚物的适宜条件:第1步反应温度为25~35℃,反应时间为2.5 h;第2步反应温度控制在75~80℃,反应时间为3 h,催化剂质量分数为0.4%.同时通过调节活性稀释剂三缩丙二醇二丙烯酸酯、三羟甲基丙烷三丙烯酸酯、1,6己二醇二丙烯酸酯的不同配比制备紫外光固化涂料,测试涂膜光泽、硬度、柔韧性、耐冲击强度、附着力等各项性能,找出涂膜具有良好弹性及柔韧性且符合光固化膜性能要求的涂料配方.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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