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1.
采用聚合度为1300的PVC树脂为基体树脂,与高分子改性剂、增塑剂、填充剂等共混研制了软质PVC密封条的粒料。通过正交试验法在软质PVC密封条配方试验中的应用,得到了制备软质PVC密封条的最佳配方。数据分析和实验结果表明当DOP为75份、填料为20份、加工助剂粉末丁腈橡胶(P83)为15份时,汽车用软质PVC密封条材料综合力学性能最好。  相似文献   

2.
1.二甘醇二苯甲酸酯合成 二甘醇二苯甲酸酯由广东石油化工高等专科学校研制。二甘醇二苯甲酸酯是优良的PVC树脂增塑剂,其性能与DOP相似,可代替DOP作为PVC树脂的主增塑剂,此外还可作为醋酸纤维素添加剂、纸品聚合物增塑剂、粘合剂添加剂、聚酯树脂拨染助剂及丙烯酸乳胶增塑剂等,广泛应用于PVC地板、  相似文献   

3.
增塑剂对PVC脆性温度的影响   总被引:1,自引:0,他引:1  
介绍了DOP、DINP、DAP等增塑剂对PVC脆性温度的影响。随着增塑剂用量的增加,PVC脆性温度一般呈下降趋势。实验发现:使用单一增塑剂时,DAP增塑剂的脆性温度较低;使用复配增塑剂时,DOA、DAP、M51增塑体系的脆性温度较低。  相似文献   

4.
采用环境友好的绿色增塑剂环氧大豆油(ESO)代替邻苯二甲酸二辛酯(DOP)对PVC进行增塑,通过调节ESO用量,考察分析PVC的拉伸断裂、动态力学及热老化性能的变化规律,并与DOP增塑的PVC产品H-70的性能进行对比.结果表明:当ESO用量为55份时,PVC的断裂拉伸强度为17 MPa,断裂伸长率为382%,玻璃化转变温度为28℃,热老化后质量损失为2.56g/m2,较H-70有显著提高.  相似文献   

5.
采用沉淀聚合法制备了低分子量苯乙烯-马来酸酐交替共聚物(SMA),并用正丁醇对其进行双酯化改性,探讨了带水剂用量、催化剂用量、酸醇物质的量比、反应温度及反应时间对SMA双酯化反应的影响。结果表明,温度为150℃,以二甲苯作为带水剂(质量分数40%)、对甲苯磺酸(p-TSA)为催化剂,通过调节催化剂用量和酸醇物质的量之比,反应5h,可制备出酯化度达72%的SMA酯化物(SME)。对SME进行热失重分析(TGA)的测试结果显示,其失重温度较SMA提前,耐热性降低。然后,将SME作为增塑剂应用于PVC螺杆挤出加工实验中,考察了不同用量SME对PVC增塑样条的力学性能及耐抽出性性能的影响并与DOP增塑剂进行了对比,结果表明SME有效改善了PVC制品的脆性,增加了其抗冲击强度,并且在化学溶剂和高温环境中均表现出良好的耐抽出性能。  相似文献   

6.
为解决常规分散染料不耐碱,造成其无法和活性染料在同浆碱性条件下印制涤棉织物的问题,采用高耐碱分散染料和活性染料进行涤棉织物同浆印花。分析了色浆中NaHCO3、六偏磷酸钠、防染盐S、尿素的用量,以及焙烘、汽蒸的温度和时间对印花织物得色量的影响,确定了最佳同浆印花工艺条件:NaHCO3质量分数为2%、六偏磷酸钠质量分数为1%、防染盐S质量分数为1%、尿素质量分数为3%;105℃下汽蒸8 min, 180℃下焙烘2 min。研究表明,耐碱分散染料/活性染料同浆碱性印花并采用汽蒸-焙烘固色工艺流程,具有工艺步骤少、流程短、节省能耗的特点,所得织物可达到传统两相法印花织物K/S值,且织物具有良好的耐摩擦色牢度和耐洗色牢度。  相似文献   

7.
采用动态硫化的方法制备了三元乙丙橡胶(EPDM)/高聚合度聚氯乙烯(HPVC)热塑性弹性体.考察了PVC聚合度、橡塑比、增塑剂添加量、硫化剂用量(质量分数)及不同促进剂配比对体系性能影响,研究了动态硫化工艺条件(硫化时间和硫化温度)对体系性能的影响.实验结果表明:采用动态硫化方法,选用HPVC、橡塑比为30/70、DOP用量为35份、硫化用量为0.4份及适当促进体系,在动态硫化温度为170研口硫化时间为6min条件下,制得性能优良的EPDM/HPVC热塑性弹性体,其拉伸强度能达到15.18 MPa,断裂伸长率能达到544%.  相似文献   

8.
水滑石填充PVC材料的热稳定性能及流动性能   总被引:17,自引:0,他引:17  
用热辊压延法制备了水滑石填充聚氯乙烯(PVC)树脂复合材料.用刚果红、热失重、Brabender扭矩流变仪等方法考察了水滑石对PVC树脂静态、动态热稳定性、流动性能的影响.结果表明,用钛酸酯改性的水滑石在PVC中效果最好;水滑石的加入可提高PVC树脂的热稳定性;随着水滑石含量的增加,PVC树脂的流动性先有所提高而后降低;水滑石在PVC树脂中最佳用量为1%~2%(质量分数).  相似文献   

9.
本文用测清晰点的方法,测定了DBP、DOP、DOTP以及DBP+DOTP等增塑剂与不同型号PVC树脂之间相互作用参数κ值,并以此讨论了增塑剂与PVC树脂的混容性能。  相似文献   

10.
探讨了利用超细涂料对纯棉毛巾织物涂料印花的工艺.对超细涂料印花的焙烘温度和时间,粘合剂用量等因素进行了单因素和正交实验的研究,结果发现粘合剂对摩擦牢度的影响最大,最佳印花工艺条件为粘合剂10%,焙烘150℃×3min.对比普通涂料与超细涂料印花效果发现,超细涂料印花织物的颜色深度大于普通涂料,具有更鲜艳的颜色和更纯正的色光,牢度和手感均好于普通涂料.  相似文献   

11.
本文针对现有阵列声波测井仪器,对井旁不同角度和不同位置井旁地质界面的全波波列进行了物理和数值模拟。结果表明,在现有仪器源距范围内,可以从全波波形中观测到清晰的反射纵波。在此基础之上,针对阵列声波全波数据特点,对Stolt的f-k偏移方法进行了改进,使其更适应于阵列声波测井需要,该方法不受地质界面倾角的限制,而且一次可以有效地处理大量现场数据,可以分别得到上倾和下倾井旁地质界面图像。最后,应用该方法对一个倾斜井的阵列声波数据进行了处理,有效的得到了井旁地层界面成像图,验证了该方法的可靠性。  相似文献   

12.
13.
Positive development of renewable energy, saving and substitution of fossil energy, promotion of the energy structure adjustment are the inevitable strategy choices of China' s sustainable development. This paper discussed the China' s bioenergy resources status, development targets and technology development roadmaps. China has 136. 140 million hm^2 of marginal land, which distribute mainly in western and northern regions. There are 1 billion t of crop residues and forestry waste annually, and 300 million t can be used to produce different kinds of bioenergies. And organic waste and manure can generate 50 billion m3 of biogas. The discussed development target indicated that it can construct a biomass oilfield with the capacity of 100 million t/year and reduce 200 million t of CO2 emission by 2020. The bioenergy technology development roadmap indicated that the bioethanol mainly uses non grain starch and hemicellulose products as raw materials in the near-term (2006 -2010). The biodiesel technology will focus on the advanced production technology, FT diesel, liquefaction of biomass and raw material production technology.  相似文献   

14.
Reservoir regulation process in the Yangtze River basin is mainly divided into two types of flood regulation and initiating benefit regulation. The present reservoir management system and operation mode are mainly for dealing with or coordinating of flood control and benefit initiation as well as benefit distribution among various beneficial functions. From the view point of river ecosystem protection, the current regulation mode has two kinds of problems : firstly, most of the reservoir regulation plans do not consider ecosystem protection at downstream of dams and needs of environment protection in reservoir areas; secondly, integrated regulation or management of water resources is ignored. It is very necessary to improve reservoir regulation mode, bearing problems faced by regulation of the Three Gorges reservoir and issues related to cascade development and regulation in Tuojiang and Minjiang River basins in mind. In accordance with the concept of scientific development, and the philosophy of "ensuring a healthy Yangtze River and promoting the harmony between human and water", taking flood control, benefit initiation and eco-system as a whole, this paper put forward the basic consideration to improve reservoir regulation as follows : on the basis of requirements of ecosystem protection at downstream of dams and needs of environment protection in reservoir areas, we should bring the functions of reservoir such as flood control and benefit initiation into full play, control the negative influence to the ecosystem at downstream of dams and the environment in reservoir areas in an endurable scope, and restore the ecosystem and the environment step by step. This paper put forward the relevant regulation process aiming at the idiographic problems such as protection of ecosystem at downstream of dams and environment in reservoir areas, protection of aquatic wildlife species and fish species, regulation of sediment and protection of wetland.  相似文献   

15.
Cordyceps sinensis (Cs) or Dongchongxiacao in Chinese is a rare and precious medicinal mushroom. In this work, a Tolypocladium sp. fungus named Cs-HK1 was isolated from a natural Cs fruiting body, and its ultraviolet (UV), infrared (IR) and high-performance liquid chromatography (HPLC) spectra all exhibited high degrees of matching to those of natural Cs, indicating the similarity of chemical composition. A crude polysaccharide (PS) fraction isolated from Cs-HKI fungal mycelium showed significant antitumor activity, inhibiting melanoma tumor growth in mice. The PS-treated mice showed significantly higher serum interferon-y (IFN-y) level and higher proliferation rate of lymphocytes ex vivo than the control animals, suggestive of the immunomodulatory activity of the PS fraction. In cell cultures, the PS fraction caused a significant and dose-dependent inhibitory effect on the proliferation of two cancer cell lines, B16/neu mouse melanoma and MDA-MB-231 human breast cancer cells, but not on normal spleen lymphocytes in vitro. Most of these bioactivities of the Cs- HK1 fungus were comparable to or even greater than those of natural Cs. The results showed that Cs-HK1 fungus may be a functional substitute for the natural Cs in health food and herbal medicine.  相似文献   

16.
The blunt snout bream(Megalobrama amblycephala)is a major aquaculture species in the Chinese freshwater polyculture system.In this study,complete diallel crossing of three strains(i.e.,Liangzi[LZ],Poyang[PY]and Yuni[YN])was used to evaluate the combining ability and heterosis effect of intraspecific crossbreeding on the growth performance(i.e.,body weight,total length,body length,body height,and Fulton’s coefficient of condition).The offspring produced from the three strains were reared in a communal pond for 20 months,and nine microsatellites were used to assess their pedigree.Of the749 offspring,708(94.53%)could be assigned directly to a single parental pair.Significant differences were observed in body weight(BW)among the different combinations,indicating that the combining ability of BW from each strain was significantly different.The general combining ability(GCA)of BW from the sire was much higher than that from the dam.The GCA for the dam and sire of the LZ and YN were the largest and the smallest,respectively.The special combining ability of YN$9 PY#was the largest,and YN$9 PY#showed significantly positive heterosis effects on all F1growth traits,except for Fulton’s condition coefficient(K)(P\0.05).In addition,significant positive linear correlations were found between the mean BW of corresponding progeny and the H E of the parental generation(y=600.7x-29.472,r=0.8651,P=0.0026),H O(y=1206.9x-518.14,r=0.7436,P=0.0216),and the polymorphism information content(y=1021.3x-331.31,r=0.8245,P=0.0063)as determined by a correlative test.The findings obtained from the study will be important for future considerations of M.amblycephala stock improvement programs.  相似文献   

17.
Objectives define the boundaries of complex engineering system. It is a hard work to identify the specific objectives of a complex engineering system. The objectives system development needs a complicated process, from nix to prototype, and to final definition. The total process will cover the following course: from chaos to well-ordered; from qualitativeness to combination of quantitativeness and qualitativenss, then from qualitativeness to quantitativeness ( a recurrent process), expert experience and theoretical science, rationality and sensibility, synthesis analysis and meta-synthesis, routinization and non-routinization. Such process is explicit in phase development yet overlapped ; mutually confined yet mutually independent ; permeated conflicts yet pregnant in harmony. This article explores the complexity of Sutong Bridge' s objectives development and the process of meta-synthesis in the Sutong Bridge engineering.  相似文献   

18.
19.
The near-surface freeze/thaw cycle in cold regions plays a major role in the surface energy budget,hydrological activity,and terrestrial ecosystems.In this study,the Community Land Model,Version 4 and a suite of high-resolution atmospheric data were used to investigate the changes in the near-surface soil freeze/thaw cycle in response to the warming on the Tibetan Plateau from1981 to 2010.The in situ observations-based validation showed that,considering the cause of scale mismatch in the comparison,the simulated soil temperature,freeze start and end dates,and freeze duration at the near-surface were reasonable.In response to the warming of the Tibetan Plateau at a rate of approximately 0.44°C decade-1,the freeze start-date became delayed at an area-mean rate of1.7 days decade-1,while the freeze end-date became advanced at an area-mean rate of 4.7 days decade-1.The delaying of the freeze start-date,which was combined with the advancing of the freeze end-date,resulted in a statistically significant shortening trend with respect to the freeze duration,at an area-mean rate of 6.4 days decade-1.Such changes would strongly affect the surface energy flux,hydrological processes,and vegetation dynamics.We also found that the rate of freeze-duration shortening at the near-surface soil layer was approximately 3.0 days decade-1lower than that at a depth of 1 m.This implied that the changes in soil freeze/thaw cycles at the near surface cannot be assumed to reflect the situation in deeper soil layers.The significant correlations between freeze duration and air temperature indicated that the shortening of the near-surface freeze duration was caused by the rise in air temperature,which occurred especially in spring,followed by autumn.These results can be used to reveal the laws governing the response of the near-surface freeze/thaw cycle to climate change and indicate related changes in permafrost.  相似文献   

20.
In this work,we developed a facile and low-cost method with sufficient sensitivity for the quantitative determination of gold nanoparticles(GNPs)number concentration in water and fetal bovine serum solutions.The Au(III)digested from GNPs was reduced to Au(I)presumably by the thiol group of 2-mercaptobenzimidazole,then the Au(I)–thiolate complex was formed,the concentration of which is determined by absorbance at 300 nm.The number concentration of GNPs can be converted using microscopic images and simple calculations.The interference of serum can be avoided in this method.The limit of detection(LOD)of GNPs was calculated as 2.1 910-12mol/L in water solution and 1.3 9 10-11mol/L in fetal bovine serum(FBS)solution.This method provides a simple and fast way to determine the concentration of GNPs,which can be in carried out in the routine laboratory practice.  相似文献   

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