首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 203 毫秒
1.
聚羧酸减水剂与水泥-粉煤灰胶凝体系的相容性研究   总被引:1,自引:0,他引:1  
采用水泥浆体流动性的实验方法,通过测量浆体流动度和观察实验现象评价高效减水剂与水泥以及粉煤灰的相容性。经过测试,聚羧酸减水剂与水泥的相容性好,并且粉煤灰对减水剂与水泥的相容性具有改善作用。聚羧酸减水剂在水泥浆体上有饱和点和离析点。各条减水剂掺量-浆体流动度曲线之间有一定的相关性。60min流动度的经时损失较30min更能反映减水剡与水泥的相容性。  相似文献   

2.
通过对掺高效减水剂水泥净浆流动性及流动性损失的测定试验,研究了高效减水剂与水泥及掺混合材水泥的相容性。试验结果表明,同一种高效减水剂与不同水泥的相容性不同;矿渣和粉煤灰都能改善水泥与高效减水剂的相容性;复掺粉煤灰和矿渣比矿渣单掺时改善效果好。  相似文献   

3.
制备了UHMWPE/PP合金材料,研究了UHMWPE/PP共混体系的流动性和力学性能及相容剂对共混体系的增容作用,研究表明:PP能有效地改善UHMWPE流动性,但与UHMWPE为不相容体系,相容剂D能够有效提高UHMWPE/PP体系的相容性,提高了材料的拉伸强度和冲击强度,达到一定的增强和增韧效果.  相似文献   

4.
《有机硅材料》2006,20(2):85-85
日前,GE-高新材料集团有机硅部推出了两款分别应用于聚氨酯软质块状泡沫和硬质泡沫的有机硅表面活性剂-Niax^*有机硅L-568和Niax^*有机硅L-6950。这两款产品解决了戊烷与多元醇的相容性差、导热系数高且能耗高、流动性差和密度分布不均匀,环戊烷或环戊烷/异环戊烷混合受到限制等问题。Niax^*有机硅L-568和L-6950具有多元醇/戊烷体系相容性好、导热系数低、泡孔细腻、流动性和密度分布好等卓越性能,  相似文献   

5.
制备了UHMWPE/PP合金材料,研究了UHMWPE/PP共混体系的流动性和力学性能及相容剂对共混体系的增容作用,研究表明:PP能有效地改善UHMWPE流动性,但与UHMWPE为不相容体系,相容剂D能够有效提高UHMWPE/PP体系的相容性,提高了材料的拉伸强度和冲击强度,达到一定的增强和增韧效果。  相似文献   

6.
制备了UHMW PE/PP合金材料,研究了UHMW PE/PP共混体系的流动性和力学性能及相容剂对共混体系的增容作用,研究表明:PP能有效地改善UHMW PE流动性,但与UHMW PE为不相容体系,相容剂D能够有效提高UHMW PE/PP体系的相容性,提高了材料的拉伸强度和冲击强度,达到一定的增强和增韧效果。  相似文献   

7.
外加剂相容性及其对混凝土性能的影响   总被引:6,自引:4,他引:2  
分析了水泥化学和物理特性、外加剂本身、掺合料的种类和掺量及集料对相容性的影响;并从外加剂的作用机理出发总结了外加剂对浆体流变性(流动性与稳定性)的影响;同时分析了相容性与混凝土耐久性之间的关系;提出良好的相容性是制备高性能混凝土的基础,对建立相容性定量评价方法做了初步探讨.  相似文献   

8.
江雪 《四川化工》2007,10(4):52-53
由大庆化工研究中心开发的改性偶联剂及其制备技术,日前获得国家发明专利。应用该技术制备的偶联剂,能有效地改进有机聚合物和无机填充物的相容性和粘合力,具有无污染、流动性好、接枝率控制精确、应用范围广等优点。  相似文献   

9.
《杭州化工》2007,37(2):43-43
大庆化工研究中心开发的改性偶联剂及其制备技术,近日获国家发明专利。用该技术制备的偶联剂,能有效地改进有机聚合物和无机填充物的相容性和黏合力,具有无污染、流动性好、接枝率控制精确、应用范围广等优点。  相似文献   

10.
贾翠  谢志鹏  刘伟  孙加林 《陶瓷学报》2011,32(2):145-149
提出了陶瓷注射成型水萃取脱脂粘结剂组分相容性的三大判断方法:溶解度参数法、热力学计算法、扫描电子显微镜法,以评判水基注射料的相容性,为陶瓷注射成型水萃取脱脂粘结剂的相容性提供了理论依据以及评判标准。并以聚乙二醇(PEG)/聚乙烯醇缩丁醛(PVB)以及聚乙二醇(PEG)/聚甲基丙烯酸甲酯(PMMA)两个水基粘结剂体系为例进行说明,讨论了陶瓷注射成型粘结剂的相容性对注射料流动性及水萃取脱脂速率的影响。  相似文献   

11.
介绍混合焓变原则和溶解度参数原则等预测聚合物合金相容性的方法,以及表征聚合物合金相容性的方法,如共同溶剂法、玻璃化转变温度法、稀溶液粘度法、显微镜法、红外光谱法、超声波技术和小角中子散射法等。指出多种表征方法的综合应用可使聚合物合金相容性的评价结果更加准确可靠。  相似文献   

12.
国内外尼龙增韧研究进展   总被引:6,自引:0,他引:6  
介绍了近年来尼龙增韧的最新研究进展,并对尼龙增韧的发展前景进行了展望,把尼龙增韧的研究划分为6类,即不同尼龙品种之间的共混、尼龙/聚烯烃、尼龙/聚烯烃弹性体、尼龙/高性能工程塑料、尼龙/无机物、尼龙/有机低分子物,列举了主要的研究工作。  相似文献   

13.
Waste tire powder was functionalized in the presence of various concentrations of allylamine and benzoyl peroxide. Fourier transform infrared spectroscopy studies confirmed the presence of allylamine on the surface of the rubber powder. The surface energy of the functionalized rubber powder revealed that the introduction of allylamine onto the rubber powder surface increased the surface activity. Improvements in the tensile strength, elongation at break, and storage modulus were observed for polypropylene/modified rubber powder/maleic anhydride grafted polypropylene, and this was attributed to an improvement in the compatibility due to the chemical interaction between the rubber powder and compatibilizer. Evidence for the reaction between the rubber surface and compatibilizer was observed in Fourier transform infrared studies. This peroxide‐initiated monomer‐grafting technique is feasible for large‐scale processes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2237–2243, 2007  相似文献   

14.
To improve the compatibility and properties of blends based on high‐density polyethylene (HDPE) and the ethylene–propylene copolymer (EPR), the functionalization of both through grafting with an itaconic acid derivative, monomethyl itaconate (MMI), was investigated. The grafting reaction was performed at 180°C in a Brabender Plasticorder using an initial monomer concentration of 3 phr in the case of HDPE and 5 phr in the case of EPR. 2,5‐Dimethyl‐2,5‐bis(tert‐butylperoxy)hexane was used as a radical initiator for the functionalization of HDPE and dicumyl peroxide was used as a radical initiator for the modification of EPR. The degree of grafting was 1.56% by weight for HDPE and 0.8% by weight for EPR. The effect of grafting on the processability, morphology, and thermal and mechanical properties of the blends are of particular interest. The results show that the grafting reaction increases the toughness and elongation at break of all tested blends and they retained their strength and stiffness. Moreover, the grafted polymers behaved as nucleating agents, accelerating the HDPE crystallization. These results are particularly relevant when both polymeric phases are modified. Morphological studies are in concordance with the mechanical characterization, showing a reduction of the rubber particle size and a better interfacial adhesion when both polymers are functionalized with MMI. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2239–2248, 2003  相似文献   

15.
聚乙烯改性的研究进展   总被引:1,自引:0,他引:1  
本文综述了聚乙烯(PE)的改性方法,包括化学和物理改性。化学改性主要包括交联、接枝和共聚改性。物理改性则包括共混、填充和增强改性。介绍了填充改性时无机填料与聚合物基体之间存在的相容性问题。叙述了各种改性对PE共混体系性能的影响。最后,简介了国内外PE改性新技术的进展。  相似文献   

16.
Malonate oligomers were synthesized as plasticizers for poly(lactic acid) (PLA). Esterification reactions were performed between diethyl bishydroxymethyl malonate (DBM) and either adipoyl dichloride or succinyl dichloride. Two molar masses were obtained within each series. Blending was carried out with PLA and the four oligomers as well as the monomeric unit from the syntheses (DBM). Dynamic mechanical analysis and differential scanning calorimetry were used to investigate the viscoelastic mechanical and thermal film properties of the blends. All the investigated plasticizers reduced the glass‐transition temperature of PLA, and the plasticization effect was better for the plasticizers of low molar mass. However, the amorphous domains of PLA became saturated with plasticizer at a certain concentration, and phase separation occurred. A higher molar mass of the plasticizer caused this saturation to occur at lower plasticizer concentrations. Subsequently, the aging of the blends at the ambient temperature for 4 months induced phase separation in the blends containing DBM, whereas those with an oligomeric plasticizer were stable and remained compatible with PLA within the aging period. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2140–2149, 2004  相似文献   

17.
The aim of the present work was to assess the blood compatibility of monomethoxy (polyethylene glycol)‐poly (D ,L ‐lactic‐co‐glycolic acid)‐monomethoxy (polyethylene glycol) (MeO‐PEG‐PLGA‐PEG‐OMe, PELGE) triblock copolymer as a propriety material for intravenous use in vitro. Three different proportional triblock copolymers were synthesized. According to the International Standard Organization (ISO) and US Pharmacopoeia XXIII recommendations, siliconized glass tube was used as the negative control sample, while nonsiliconized glass tube was used as the positive control. The blood compatibility of the films of poly (D ,L ‐lactic and glycolic acid) (PLGA) was evaluated by dynamic clotting time, activated partial thromboplastin time (APTT), and plasma recalcification time (PRT) measurements, platelet adhesion investigation, and hemolytic ratio analysis. The results revealed that blood compatibility of the materials was good. Nanoparticles made by this kind of materials might be promising for intravenous use. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1019–1023, 2006  相似文献   

18.
Ultrasonic spectroscopy provided a powerful, efficient, and reliable tool for a number of investigations, including those of polymer solution dynamics, molecular interaction, and the miscibility and compatibility of biopolymers in aqueous solutions. Ultrasonic velocity and related acoustic parameters were measured as a function of the concentration of poly(vinyl alcohol) (PVA), dextran, and a PVA–dextran mixture in water with the resonance method at a frequency of 3 MHz over a temperature range of 20–50°C. From the comparative results of sound velocity, density, adiabatic compressibility, acoustic impedance, and viscosity relaxation time as a function of temperature and concentration, the mode of interaction and the compatibility and miscibility between the two biologically active macromolecules were probed and were considerable at all concentrations and temperatures because of crosslinking via hydrogen bonding involving the hydroxyl groups of both of the biomacromolecules. The interpretations of the acoustic results were confirmed by the intrinsic viscosities of the ternary systems. The significant interaction and compatibility of these biopolymers should lead to the development of pharmaceutically active molecules. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 3196–3201, 2003  相似文献   

19.
The thermal and rheological behavior of blends of a Fischer–Tropsch (F-T) wax with linear low-density polyethylene (LLDPE) were investigated by differential scanning calorimetry and cone-and-plate rheometry. F-T wax is used as a possible low-cost processing aid alternative for LLDPE masterbatch applications. The melting- and crystallization thermograms indicated a two-phase solid-state morphology and full compatibility in the fully molten material. Both the high-melting and low-melting phase contained co-crystalized wax and polymer. Rheological data of F-T wax-LLDPE blends over the full composition range was also obtained. The zero-shear viscosity data was adequately predicted by the Friedman and Porter mixing rule: η = w p η p 1 / α + w w η w 1 / α α with α = 3.4. This implies that the melt viscosity is dominated by the effects of polymer chain entanglement and that the main consequence of adding the wax is to reduce the concentration of the polymer present. The complex viscosity also fitted this model albeit with α = 4.81. All Han plots, that is, plots of the logarithm of the storage modulus (G') against the logarithm of the loss modulus (G"), were linear. Within the experimental uncertainty, they were essentially unaffected by variations in blend composition, temperature and the applied angular frequency. Additionally, Cole–Cole plots were also in agreement that wax-LLDPE blends are miscible at melt state. This supports full miscibility of the F-T wax-LLDPE blend system down to temperatures as low as 120°C.  相似文献   

20.
共聚物作为增容剂的研究综述   总被引:3,自引:0,他引:3  
对接枝或嵌段共聚物作为非反应性增容剂的研究作了综述。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号