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1.
在合成聚氨酯的基础上,以二溴新戊二醇与三羟甲基丙烷扩链合成具有阻燃、热防护性能的反应型水性聚氨酯.通过红外光谱、DSC、TG及扫描电镜等表征水性聚氨酯,并通过涂层整理与浸轧整理的性质测试以确定最佳合成工艺.最后确定以聚丙二醇与异佛尔酮二异氰酸酯进行预聚反应,预聚温度80℃,选择80℃为扩连温度,R值选择1.2,DMPA含量5%左右,TMP反应温度为70℃,中和度120%合成水性聚氨酯热防护整理剂.该条件下合成产物阻燃和热防护性能效果最佳.  相似文献   

2.
文采用HDI、聚环氧丙烷二醇、二羟甲基丙酸和封端剂乙二醇等为原料通过预聚法合成水性聚氨酯,并对其成膜性进行了力学分析.通过比较,最佳制备工艺:在40℃时向聚环氧丙烷二醇中缓慢加入HDI,80℃预聚1h,加催化剂再反应1h降温至75℃,加DMPA反应2h, 再封端反应1h,降温至35~40℃加入TEA乳化30min.交联剂相对含量的提高,可以提高聚氨酯膜的强度和韧性.  相似文献   

3.
采用预聚体法,以聚醚多元醇,六亚甲基二异氰酸酯(HDI),N-甲基二乙醇胺(MDEA)为原料制备了阳离子水性聚氨酯乳液,采用正交法分析考察了R(n-NCO/nOH)值、饱和度、MDEA用量、封端剂对水性聚氨酯乳液性能的影响,并探究了焙烘温度和焙烘时间对固色效果的影响,并与市售产品进行固色效果的比较.结果表明,在R值为2. 5、MDEA含量为7. 5%、冰醋酸为中和剂、乙二醇用量为100%、环氧氯丙烷作为封端交联剂用量为100%时,所合成的阳离子水性聚氨酯乳液具有较好的固色效果,用于整理聚氨酯(PU)革的最优焙烘温度为120℃,焙烘时间为10 min,可提高PU革的干、湿摩擦牢度2~3级,与市售产品的固色效果相当.  相似文献   

4.
阳离子型水性聚氨酯的研制   总被引:1,自引:0,他引:1  
以聚乙二醇(PEG)、甲苯二异氰酸酯(TDI)、N-甲基二乙醇胺(MDEA)为主要原料,用自乳化法合成了阳离子型水性聚氨酯;探讨了合成反应工艺条件.研究表明,较佳的合成工艺条件为:制备预聚物时n(NCO)/n(OH)比值为3:1;以N—甲基二乙醇胺为扩链剂,采用“饥饿加料”方式,其用量为预聚物质量分数的5.0%~6.0%;预聚物合成反应温度为60℃,反应时间3 h;扩链反应的反应温度40℃,反应时间5 h;中和度为80%~100%.在此工艺条件下,合成的阳离子型水性聚氨酯具有良好的稳定性能.  相似文献   

5.
以不同链长的PTMC-OH为软段,IPDI、DMBA等为硬段,通过逐步聚合法合成了具有嵌段结构的水性聚氨酯(Waterborne Polyurethane, WPU)乳液及膜,并检测了WPU乳液及膜的性能.结果表明,WPU乳液的固体质量分数达36%,黏度和p H符合工业化产品要求;中位粒径在135 nm左右且粒径分布较窄.乳液稳定性好,可直接应用于水基材料领域.另一方面,WPU膜的相对分子质量随PTMC-OH相对分子质量的增大而增大;WPU膜的水接触角均小于90°,呈亲水性;WPU膜的断裂伸长率达247.27%~941.53%,是一种软而韧的聚合物;WPU膜的初始分解温度在250~260℃,耐热性优异.合成出的WPU综合性能好且安全环保,有望取代传统溶剂型聚氨酯在涂料、油墨和胶粘剂等领域有广阔的应用前景.  相似文献   

6.
以异佛尔酮二异氰酸酯(IPDI)、4,4_二环己基甲烷二异氰酸酯(HMDI)、聚醚二元醇( PTMEG_2000)为单体,用N_甲基二乙醇胺作亲水扩链剂,制备阳离子型水性聚氨酯( WPU),并对其进行了红外光谱和粒径分析,主要探讨了影响阳离子水性聚氨酯固含量、断裂伸长率、吸水率的因素如混合二异氰酸酯摩尔比n ( IPDI/HMDI )、预聚时二异氰酸酯与二元醇摩尔比n(二异氰酸酯/二元醇)、N_甲基二乙醇胺用量、三羟甲基丙烷用量和中和度.结果表明:当n( IPDI/HMDI)在0.47:1与0.23:1之间时,所制得的阳离子型水性聚氨酯的固含量、断裂伸长率和吸水率均呈较稳定的状态;预聚阶段n(二异氰酸酯/二元醇)对WPU固含量影响不大,对断裂伸长率、吸水率影响明显;MDEA的用量对固含量、断裂伸长率和吸水率都有较深的影响;TMP的用量对WPU膜的固含量、吸水率及断裂伸长率影响一般;中和度对WPU固含量以及断裂伸长率的影响不大,但对吸水率影响较大.  相似文献   

7.
采用甲苯二异氰酸酯(TDI)、聚酯多元醇和二羟甲基丙酸(DMPA)为主要原料,经分步预聚后在水中自乳化合成了阴离子型水性聚氨酯.探讨了合成工艺路线,研究了NCO/OH比例、DMPA含量等对水性聚氨酯乳液性能的影响.结果表明:当NCO/OH值选择在1.5~2.3,DMPA用量为3%~8%时,乳液性能最佳.  相似文献   

8.
将丙烯酸异冰片酯(IBOA)和二乙醇胺(DEA)反应,合成了一种新颖的带有刚性环结构的单体3-(N,N-二羟乙基氨基)丙酸异冰片酯(DEAIBOA),然后将DEAIBOA引入水性有机硅聚氨酯丙烯酸酯分子中,合成了一系列具有不同刚性环含量的有机硅聚氨酯丙烯酸酯水性低聚物(IBOA-WSPUA)。系统研究了低聚物中刚性环含量对乳液稳定性、光聚合性能及其固化膜的物理力学性能、玻璃化转变温度和附着力的影响,结果表明:所合成的5种低聚物的分子量均接近单分散,粒径分布均匀,具有良好的乳液稳定性及光聚合性能,双键的最终转化率均在85%以上;随刚性环含量的增加,低聚物固化膜的拉伸强度、玻璃化转变温度和铅笔硬度逐渐增大;低聚物固化膜的附着力得到明显改善,在聚碳酸酯(PC)、丙烯腈-丁二烯-苯乙烯共聚物(ABS)及玻璃基材上均达到5B。  相似文献   

9.
以异氰酸酯和多元醇为原料,合成了聚氨酯预聚体,经过扩链反应制备了自乳化水性聚氨酯聚合物。通过水兮散工艺得到水性聚氨酯乳液。测定了合成过程中异氰酸酯基(-NCO)的含量,使用红外光谱对合成的水性聚氨酯聚合物进行了结构表征,实验研究了水性聚氨酯乳液的性能变化等关系。  相似文献   

10.
通过引入不同含量的2,2-双(羟甲基)丙烯酸丁酯(HBA),合成了一系列不同双键含量的可光聚合含硅聚氨酯丙烯酸酯水性低聚物(HBA-WSiPUA),它们均可以形成稳定的白色乳液,且粒径分布均匀。详细研究了低聚物中双键含量对低聚物的光聚合行为和光固化膜的热性能、物理力学性能及表面性能的影响,结果表明:所合成的低聚物的最终双键转化率均在90%以上;随着双键含量增加,光固化膜的拉伸强度、硬度、初始分解温度和玻璃化转变温度都随之增加,最高分别可达15.2 MPa、6H、286 ℃和80 ℃,而光固化膜的断裂伸长率、表面水接触角和吸水率则随之降低,吸水率最低可至2.5%。  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.
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   

16.
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   

17.
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   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
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   

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