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1.
松香水溶性树脂的制备研究   总被引:5,自引:0,他引:5  
以松香为原料 ,经马来酸酐、无水哌嗪改性制成松香聚酰胺 ,再与多元醇酯化 ,制备 8种松香水溶性树脂 ,其中 2种产品的软化点高 ,水溶液稳定性好 ,适宜于配制水性油墨。讨论了影响产品性能的主要因素 :反应温度、多元醇种类和马来酸酐用量  相似文献   

2.
以油脂下脚料酸化油为原料,通过与顺丁烯二酸酐加成,再与二甘醇酯化,得到聚酯多元醇,其最佳工艺条件为:M(酸化油)∶M(顺丁烯二酸酐)∶M(二甘醇)=1∶1∶3.3;顺丁烯二酸酐在180℃、195~200℃、200~220℃分3次加入,各反应1 h,在230~240℃下反应0.5 h;240℃下常压酯化10 h;240℃减压酯化1 h。合成的聚酯多元醇酸值小于1 mg/g,羟值在250~300 mg/g。以合成的聚酯多元醇为原料,制备的双组分聚氨酯胶粘剂性能可以达到彩钢板与聚苯乙烯泡沫塑料的胶合工艺要求。  相似文献   

3.
基于酸式磷酸酯树脂(PRA)固化氨基树脂(MUF)制得水性膨胀型阻燃清漆(WBIFRV),研究了新戊二醇(NPG),三羟甲基丙烷(TMP)和季戊四醇(PT)等多元醇做醚化剂对漆膜性能的影响.实验结果表明:多元醇的引入使氨基树脂的存储稳定性和漆膜防火性能得到提高,但会恶化漆膜耐水性.  相似文献   

4.
预聚型聚氨酯涂料的研制   总被引:1,自引:0,他引:1  
由松香及二甘醇等合成醇酸树脂多元醇与TDI反应制备了预聚型聚酯涂料,讨论了醇酸树脂多元醇、氨酯化反应的工艺等因素对聚氨酯涂料性能的影响,性能测试表明,该漆干燥速度快,理化性能优异,质优价廉,具有广阔的应用前景。  相似文献   

5.
棕榈油是一种天然可再生的植物油,将其转化为棕榈油多元醇可作为聚氨酯的原料.以棕榈油为原料,研究了棕榈油多元醇的酯基胺解合成工艺,确定了反应温度、反应时间及催化剂用量等制备条件:常压80℃,反应2 h,催化剂加入量为1.5%.并利用红外光谱、液相色谱和热重分析对所得产物的结构和性能进行了表征.采用本方法合成的棕榈油多元醇具有纯度较高和较好热稳定性.  相似文献   

6.
由于聚酯大分子结构缺少极性吸湿基团,其亲水性尚待改善.以精对苯二甲酸(PTA)和乙二醇(EG)为基本单体,以间苯二甲酸双羟乙酯-5-磺酸钠(SIPE)为第三单体、聚乙二醇(PEG)为第四单体以及多元醇为第五单体,采用酯化和缩聚反应制备得到具有高亲水性的共聚酯,并通过傅里叶变换红外光谱(FTIR)、差示扫描量热仪(DSC)、热失重分析仪(TGA)、接触角测试仪(CA)和纤维强力仪对亲水共聚酯的结构与性能进行表征.结果表明:亲水共聚酯由于含有多羟基结构,而赋予其以优异的亲水性能,并且由于多元醇的引入,破坏了其结构的整体规整性,因此结晶性变差,且熔点降低;同时多羟基结构导致亲水共聚酯的耐热温度低于纯聚酯.通过熔融纺丝得到的亲水共聚酯具有良好的可纺性,并且亲水共聚酯纤维吸湿性好,纤维强度可以满足家纺要求.  相似文献   

7.
以废旧聚氨酯制品为主要原料,利用醇解工艺将其降解得到低聚物多元醇,确定出最佳的降解工艺并成功制备了新型聚氨酯保温材料。利用红外光谱仪(FTIR),热重分析仪(TG)和偏光显微镜测试仪器对材料进行测试分析,结果表明,废旧聚氨酯制品的降解产物能够制备聚氨酯保温材料且耐热性能稳定,其泡孔的分布均匀致密,保温效果良好。  相似文献   

8.
在催化剂作用下以烷基多苷(简称APG)和马来酸酐为原料进行酯化,然后以亚硫酸铵为磺化试剂对酯化产物进行磺化,制备了烷基多苷磺基琥珀酸单酯二铵盐(APG-SA)。重点考察了反应温度、时间、马来酸酐酐与亚硫酸铵的摩尔比等对磺化反应的影响,确定了较佳工艺条件。测定了产品的表面物性,证明APG-SA在表面张力、乳化、渗透和泡沫性方面具有较好的性能,尤其在乳化方面,和烷基多苷、烷基多苷磺基琥珀酸单酯二钠盐(APG-SS)相比,具有更优良的性能。  相似文献   

9.
以聚酯二元醇、甲苯二异氰酸酯(TDI)、二羟甲基丙酸(DMPA)、1,4-丁二醇(BDO)和三羟甲基丙烷(TMP)等为原料合成了双组分水性聚氨酯(WPU)的多元醇组分.考虑到溶解性、反应活性、工业成本等因素,本研究从小分子二元醇(如乙二醇、丙二醇、丁二醇、一缩乙二醇等),小分子三元醇(甘油),小分子四元醇(季戊四醇),聚乙二醇(相对分子质量200~2 000),聚丙二醇(相对分子质量300~2 000)等数十种醇类化合物中,反复试验,再三筛选,最后确定以聚乙二醇-800和六亚甲基二异氰酸酯(HDI)三聚体为原料合成了亲水性多异氰酸酯固化剂组分.将多元醇组分和固化剂组分混合配制,得到了双组分WPU胶黏剂.通过红外光谱(FT-IR)、核磁共振(NMR)、黏度、吸水率、黏接强度、离心稳定性等性能测试,分别对多元醇组分和固化剂组分合成的关键步骤及影响产物性能的各种因素进行了探讨.结果表明,当DMPA、BDO、TMP的质量分数分别为6%、4%、3%时,多元醇组分的外观、稳定性、黏接强度等性能较好;选择聚乙二醇作为亲水组分对HDI三聚体进行改性,且当其添加的质量分数为11%及以上时,制备出的多异氰酸酯固化剂组分具有较好的水分散性.  相似文献   

10.
驱油用石油磺酸盐的合成与性能评价   总被引:5,自引:0,他引:5  
以发烟硫酸为磺化剂进行磺化反应,制备了石油磺酸盐.通过对原料性质、反应时间、反应温度对产品性能影响的考察,筛选出最佳的实验原料及制备的工艺条件.研究表明,磺化反应条件选取温度为40℃、反应时间为60min时,可以得到性能优良的石油磺酸盐产品.以海洋混合减一线油、辽河减四线油为原料制得的石油磺酸盐产品,提纯后具有较好的表面张力和界面性质.  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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