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1.
高磺化度SEPDM的制备及离聚体性能研究   总被引:6,自引:0,他引:6  
研究了磺化度大于0.5mol/kg的磺化三元乙丙橡胶的制备及离聚体的加工和力学性能,讨论了磺化反应的影响因素,得到了优化的横化反应条件:n(乙酸酐):n(浓硫酸)=1:1,5℃下反应30min。硬脂酸锌是高磺化度SPDMZn离聚体的有效增塑剂,其质量分数为10%-30%时,可显著改善离聚体的加工性能。  相似文献   

2.
用差示扫描量热分析(DSC)和宽角X_射线衍射(WAXD)等方法研究了离子含量为2.2×10-2摩尔分数的磺化聚苯乙烯锌盐(ZnSPS)离聚体对间规聚苯乙烯(sPS)结晶的共混效应.结果表明,在所研究的共混物比例组成范围内,虽然sPS的结晶速率随ZnSPS混入量的增多而下降,但sPS的结晶成核生长方式,总结晶程度和结晶规整度等则基本上不受ZnSPS的影响.代表sPSβ晶型晶体的特征衍射峰强度随ZnSPS混入量的增多而下降,表明ZnSPS的混入使sPSβ晶型晶体的生长受到抑制,α晶型晶体的含量相对增加  相似文献   

3.
磺化聚苯乙烯/聚氨酯共混体系的力学性能及形态结构   总被引:2,自引:0,他引:2  
用电子拉力机、MDSC,FTIR、SEM、SAXS研究了磺化聚苯乙烯(SPS)/聚醚型聚氨酯(PU)共体系撂学性能和形态结构。结果表明,在溶液法制备的含磺酸基12.8%(摩尔)的SPS/PU共混体系中,SPS含量小于80%(质量)时,共混物的拉伸强度小于加和性计算值,吾抵消效应;SPS含量大于80%时,则呈协同效应,拉伸强度协同效应产生的原因是由于共混组分间离子交 形成以及分子间相互作用力增大,共  相似文献   

4.
聚苯胺(PAn)具有较高的室温电导率,但难于加工成型.锌盐离聚体具有较好的力学性能,An在锌盐离聚体颗粒表面吸附聚合,可以得到电导率达10.5S·cm(-1),抗拉强度为6.11MPa的新型导电复合物.经TEM研究其表明,证实该复合物为所需合成的PAn复合物.  相似文献   

5.
以环己烷为溶剂、浓硫酸和丙酸酐为磺化剂,制备了磺化聚苯乙烯离聚体。FT—IR谱留证明磺化反应是成功的。研究了磺化条件的影响,确认磺化反应的最佳条件为:浓硫酸:丙酸酐=1:1(mol);23K下,磺化时间为2小时。热分析结果表明,本方法制备的离聚体的玻璃化转变温度与离子含量无关,表现出类似于嵌段共聚物的特点。  相似文献   

6.
用溶液法制备顺酐化聚丙烯(MPP)及用熔融和溶液两种方法中和得到了顺酐化聚丙烯离聚体,并研究了它们的力学性能.结果表明:对于聚丙烯顺酐化,当顺丁烯二酸酐(MAH)占反应物的7.1%时,产物中MAH结合量为6.8%,利用率最高,达到95.8%.用溶液法中和得到的离聚体其拉伸强度比用熔融法得到的大,且拉伸强度随顺酐结合量的增大,先增大后减小,出现极大值,中和度达到125%时拉伸强度和冲击强度都达到最大值.一价金属离子离聚体的拉伸强度比二价金属离子离聚体的小,所有离聚体的拉伸强度及抗冲强度明显优于聚丙烯(PP).  相似文献   

7.
合成了分别含Li ̄+,Na ̄+,K ̄+和Mg ̄(2+),Ca ̄(2+),Ba ̄(2+)的6种乙丙三元胶(EPDM)磺酸盐离聚体,溶解性试验反映出固体中存在聚集引起的离子交联,红外光谱表明金属离子与的相互作用为Li ̄+>Na ̄+>K ̄+和Mg ̄(2+)>Ca ̄(2+)>Ba ̄(2+)及M ̄(2+)>M ̄+,通过动态力学分析,讨论了离聚体中离子相互作用对离子聚集和橡胶平台区温度范围的影响规律。  相似文献   

8.
离聚体法制备复合纳米微粒   总被引:1,自引:0,他引:1  
用碳酸稀土和马来酸酐合成马来酸稀土单体后,通过乳液聚合成功地制备了含稀土的聚苯乙烯-马来酸离聚体,在离聚体中,离子基团在碳链低极性介质中聚集,最终形成了离子簇-纳米微粒,采用透射电镜(TEM),傅立叶红外(FTIR)及X-射线光电子能谱(XPS)等对这种纳米微粒的结构和性能进行了表征,并在四球试验机上考察了其用作润滑油添加剂的润滑性能。  相似文献   

9.
用Ag_2S和CuS以8∶1(或14∶3)的比混合物做为活性物质,用邻苯二甲酸二辛酯(DOP)为增塑剂。首次研制了非均相PVC膜铜离子选择性电极,电极的能斯特响应范围为5.0×10 ̄(-6)~1.0×10 ̄(-2)mol·L ̄(-1),平均斜率为30mV/PCU(25℃),电极的重现性和稳定性都比较好,电极的寿命可达三个月。用试制的PVC膜铜离子选择性电极测定了铜合金中铜的含量与经典法碘量法所得结果相吻合,还用试制的电极测定了标准精镁试样中微量铜的含量与标准值一致。  相似文献   

10.
本文研究了用溶液法制备顺酐化聚丙烯(MPP)及用熔融方法中和得到的顺酐化聚丙烯离聚体的加工性能。结果表明:随顺酐加入量的增加,聚丙烯(PP)中顺酐结合含量增加,但利用率先增大后减小,出现极大值。最佳混炼温度时,聚丙烯离聚体比PPY同,二价离子的离聚体比一介离子的稍高。顺酐含量越高离聚体的加工性越差。增塑剂硬脂酸锌对离聚体的成型性有显著影响。  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
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   

19.
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   

20.
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   

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