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1.
合成一种含P、Si协同阻燃的新型嵌段共聚物,将合成的阻燃嵌段共聚物分散于双酚A型环氧树脂E51中,以4,4′-二氨基二苯甲烷(DDM)为固化剂,制备了一系列不同P、Si含量的阻燃环氧树脂.采用扫描电镜(SEM)对改性环氧树脂断面进行观察,通过动态力学热分析(DMTA)、差示扫描量热法(DSC)、热失重分析(TGA)及氧指数(LOI)对改性环氧树脂进行性能测试.结果表明:合成的含P、Si新型嵌段共聚物在环氧树脂中能够自组装形成以多面体齐聚半硅氧烷(POSS)链段为核、含磷嵌段为壳的纳米核壳结构,阻燃元素P、Si以"捆绑式"均匀分散在环氧基体中,达到低P、Si含量下优良的协同阻燃效果.此外,添加阻燃嵌段共聚物还能够有效提高环氧树脂热稳定性.  相似文献   

2.
酸改性环氧树脂可用于印制电路板(PCB)基材上的阻焊油墨.传统的二步法合成酸改性环氧树脂,反应过程不好控制,容易产生凝胶.本文以反丁烯二酸、丙烯酸为改性剂,采用一步合成法,在双酚A环氧树脂上接枝羧基及带双键的光敏基团,制备UV固化酸改性环氧树脂.通过傅里叶转换红外光谱分析(FTIR)、凝胶渗透色谱(GPC)、超声波显微分析(SAM)、色差分析、热老化分析等表征,结果表明:采用一步法合成的酸改性环氧树脂的平均分子量更大分布更加均匀,固化后机械综合性能、耐热老化性能等均好于二步法合成酸改性环氧树脂工艺,并较好解决了二步法工艺容易凝胶的问题.  相似文献   

3.
以八甲基环四硅氧烷(D4)和N–β–氨乙基–γ–氨丙基甲基二甲氧基硅烷(KH–602)为原料,用(CH3)4NOH作为催化剂,低粘度二甲基硅氧烷为封端剂,采用本体阴离子聚合法合成了侧氨基改性聚硅氧烷,并对其结构用红外光谱与紫外光谱进行了表征.研究了制备过程中聚合时间、KH–602、封端剂及催化剂用量等对氨基硅油技术指标的影响,得到了完整的工艺配方.  相似文献   

4.
4,4′-二氨基苯甲酸苯酯(4-aminophenyl-4′-aminobenzoate,简称 AAB)可用于制备热塑性橡胶、聚酰亚胺和多种含硅化合物■.AAB 与环氧氯丙烷反应可以合成一种新的环氧树脂.  相似文献   

5.
为改善双酚A型环氧树脂的耐热性,采用二苯基硅二醇单体与环氧树脂E-44直接开环加成聚合的方法.以辛酸亚锡作催化剂、4,4'-二氨基二苯基砜(DDS)为固化剂,研究了反应条件和E-44与二苯基硅二醇的物质的量配比对改性产物耐热性能的影响.通过傅立叶红外光谱仪(FT-IR)、动态热机械仪(DMTA)、热失重分析仪(TGA)进行分析,得出最佳反应条件是150℃/2h,配比为3:1时,改性环氧树脂的玻璃化转变温度(Tg)为147.45℃,分解温度(Td)达到490.5℃(热失重50%).实验结果表明:二苯基硅二醇改性可以提高环氧树脂的耐热性能.  相似文献   

6.
以4,6-二氨基间苯二酚盐酸盐和对苯二甲酸为原料,制备了4,6-二氨基间苯二酚-对苯二甲酸盐(TA盐),并采用傅里叶红外(FTIR)、质谱(MS)、差热分析(DSC)和元素分析等测试手段对其结构进行了表征;以多聚磷酸为介质,将TA盐缩聚得到具有较高粘度(特性粘数[η]=24.5dL/g)的聚苯撑苯并二恶唑(PBO),并通过FTIR、元素分析和热重分析(TGA)等对PBO合成工艺和热性能进行了研究.这种通过TA盐聚合的方法不仅缩短了反应时间,而且比较容易得到具有较高相对分子质量的PBO.  相似文献   

7.
含有硅氧链的胺类化合物的合成   总被引:4,自引:0,他引:4  
采用二甲基二氯硅烷与羟基硅油合成一定链长的含氯硅油,再与胶类合成有机硅氧键的胶类化合物,用作环氧树脂固化剂,具有显著的增韧改性效果.  相似文献   

8.
胜利100号沥青合成改性COPNA树脂   总被引:2,自引:0,他引:2  
以胜利100号沥青为原料合成了改性COPNA树脂,改性COPNA树脂需要在COPNA树脂的侧链上接入含-Si(Oet),基团的偶联剂分子,以使其比改性前对石英砂具有较强的亲和性、较高的热稳定性及抗压强度.试验考察了改性COPNA树脂的合成条件、溶解性、热稳定性和固砂性能等.实验中,选择“南大-42”为硅烷偶联剂,“COPNA树脂与偶联剂”的质量比例为“200:0.5”,于85~90℃温度下,搅拌反应6h,生成改性COPNA-B树脂;以苯甲醛为固化剂,可使得改性COPNA树脂在400℃以下时,具有较高的热稳定性及抗压强度.试验表明,改性COPNA树脂可用作高温油井防砂材料和稠油热采防砂材料.  相似文献   

9.
由羟基香茅醛合成了多元醇3,7-二甲基-2,2-二羟甲基-1,6辛二醇并由它合成了螺环原碳酸酯单体3、9-二羟甲基-二(6-甲基-5-羟基)-2-庚基-1,5,7,11四氧杂螺环[5、5]十一烷单体以及它的预聚体,并用其来改性酚醛环氧树脂F-44.利用红外光谱对多元醇。螺环单体及预聚体进行了表征.依据DSC测试结果确定了固化温度:利用万能材料实验机测试了固化改性酚醛环氧树脂的力学性能.实验表明。预聚体的加入提高了酚醛环氧树脂的剪切强度和拉伸强度.  相似文献   

10.
改性氨基聚硅氧烷膜与膜形貌及应用   总被引:1,自引:0,他引:1  
用原子力显微镜(AFM)和接触角测量仪对乙酸酐改性氨基聚硅氧烷的成膜性及膜形态进行了研究。结果发现,氨基聚硅氧烷在单晶硅基底上均能成膜,但不同氨基聚硅氧烷所形成的膜形貌是不同的,膜的表面形貌实际上与基团的排列方式有关,氨乙基氨丙基聚二甲基硅氧烷在单晶硅基底上形成均匀、平整、光滑的疏水膜;而乙酸酐改性的氨乙基氨丙基聚二甲基硅氧烷则形成凹凸不平、粗糙的具有弱亲水性的非均匀膜。  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.
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   

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 discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
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   

16.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

17.
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   

18.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

19.
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   

20.
赵英华 《科技信息》2008,(12):219-220
0.Preface China has long been boasting of its colorful and immense culture which comprises of Taoism,Confucianism and Buddhism.The interwoven influence among the religions on Chinese way of thinking,on the nation's behavior in their social life throughout the long history is beyond list.  相似文献   

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