Effect of different montmorillonites on rheological properties of bitumen/clay nanocomposites

Different composites of organomodified montmorillonite(OMMT)/bitumen were prepared by melt blending with hexadecyl dimethyl benzyl ammonium modified montmorillonite(HBM) and double octadecyl dimethyl ammonium modified montmorillonite(DOM).The structures of two kinds of montmorillonite modified bitumen were characterized by X-ray diffraction(XRD).The effects of different montmorillonites on the dynamic rheological properties of the modified bitumens were investigated by dynamic shear rheometer(DSR).The XRD results show that DOM modified bitumen forms an intercalated structure,whereas the HBM modified bitumen forms an exfoliated structure.DSR results indicate that OMMT modified bitumens exhibit higher complex modulus,lower phase angle than pristine bitumen,which means that the resistance to rutting at high temperatures of pristine bitumen is improved due to the introduction of OMMT.Compared with DOM modified bitumen,HBM modified bitumen shows better rutting resistance,which is contributed to the formation of exfoliated structure in HBM modified bitumen.     

熔融插层法制备累托石/聚碳酸亚丙酯纳米复合材料的研究

采用熔融插层法制备了有机化累托石/聚碳酸亚丙酯纳米复合材料,通过X射线衍射、原子力显微镜、热重分析法测试了复合材料的结构与热性能。结果表明:聚碳酸亚丙酯能插层于累托石片层中,累托石/聚碳酸亚丙酯纳米复合材料的耐热性有了很大程度的提高。     

有机温拌剂对SBS改性沥青及其混合料性能的影响研究

研究了SKW有机温拌剂对SBS改性沥青的物理性能、润湿性能以及对SBS改性沥青混合料性能的影响。结果表明,该温拌剂明显增大了SBS改性沥青的针入度和延度,显著降低了其135℃时的粘度,并提高了其与集料之间的润湿性,而对软化点的影响很小。当温拌剂的掺量为沥青用量的2%时,SBS改性沥青混合料的拌合温度和压实温度可分别降低25℃和35℃,而温拌SBS改性沥青混合料的体积性能、水稳定性和高温稳定性与热拌SBS改性沥青混合料相当。     

Mg-Al LDHs改性沥青的制备与抗老化性能研究

将镁铝基层状双氢氧化物(Mg-Al LDHs)与基质沥青熔融共混,制备了Mg-Al LDHs改性沥青。采用薄膜烘箱试验(TFOT)和紫外光老化试验分别研究了不同掺量的Mg-Al LDHs对沥青短期热氧老化和紫外光老化性能的影响。结果表明,Mg-Al LDHs可有效抑制沥青在TFOT和紫外光老化过程中软化点和粘度的增加,显著提高沥青延度保留率,减小其质量变化,有效改善了沥青抗短期热氧老化和紫外光老化性能。     

INTERFACE REACTION BETWEEN γ-AMINOPROPYLTRIMETHOXYSILANE AND ULTRAVIOLET IRRADIATED POLYPROPYLENE

The interface reaction between ultraviolet irradiated polypropylene (UV-PP) and an amino silane coupling agent, Y-aminopropyltrimethoxysilane (Y-APS) adsorbed on glass fibers has been investigated by means of the combining use of solvent extraction and FTIR as well as XPS. First, polypropylene (PP) physisorbed on the glass fibers surface was removed by the solvent extraction in order to minimize the effect of the PP siginal in FTIR and XPS analyses. Second, the remaining glass fibers after solvent extraction were analyzed by FTIR and XPS. The results show that the absorption bands of PP still exist in the FTIR spectrum and two new bands of N1s at 399. 6ev and 401. 6eV appear in the XPS spectrum for the composite with UV-PP and Y-APS treated glass fibers. Thus, the interface reaction between the UV-PP and Y-APS has been monitored directly. In addition, it may be concluded that OH and COOH groups of UV-PP form chemical bonds with NH_2 group of Y-APS, respectively.     

渗克宝渗透结晶型掺和剂对混凝土耐化学侵蚀和冻融循环的影响

对加入渗克宝渗透结晶型掺和剂的砂浆试件进行吸水率、耐化学侵蚀和冻融循环测试,研究了添加掺和剂对前后试件的吸水率、抗压强度和抗渗压力的影响。结果表明:渗克宝渗透结晶型掺和剂可以有效防止水的侵入,明显降低水泥基材料的吸水率;赋予混凝土优良的耐化学侵蚀和抗冻融循环能力,提高混凝土的耐久性。     

在不同介质条件下渗透结晶型防水涂料对水泥基材料性能的影响

研究了在纯水、硫化氢溶液、氨水溶液、硫化铵溶液等不同介质条件下渗透结晶型防水涂料对砂浆强度、吸水率和裂缝自愈合能力的影响。结果表明:经上述4种介质处理,涂刷渗透结晶型防水涂料的砂浆试样抗压强度均高于普通砂浆试样,吸水率则明显小于普通砂浆试样;与纯水相比,硫化氢溶液和硫化铵溶液不影响渗透结晶型防水涂料裂缝自愈合功能的发挥,而氨水溶液对其功能的发挥有一定的不利影响。     

制备工艺对LDHs-SBS改性沥青性能的影响研究

采用熔融混合法制备了层状双羟基复合金属氢氧化物(LDHs)-SBS改性沥青,研究了共混温度、共混时间和分散方式等工艺条件对LDHs-SBS改性沥青性能的影响,确定了LDHs-SBS改性沥青适宜的制备工艺条件,并探讨了分散方式与LDHs-SBS改性沥青耐老化性能之间的关系.     

沥青混凝土生命周期环境影响评价研究

沥青混凝土在生产、铺筑和废弃过程中会消耗大量的自然资源和能源,因此有必要对其开展生命周期环境影响评价.采用生命周期评价方法,对沥青混凝土生命周期过程中的资源、能源消耗及污染物排放进行了评价.结果表明,沥青混凝土生命周期中能耗最大的是拌和过程,环境负荷影响类型重要性的大小依次为:不可再生资源＞温室效应＞酸化效应＞光化学烟雾＞人体健康损害;不同生产阶段的环境影响大小依次为:原材料生产过程＞运输过程＞拌和过程＞废弃过程＞摊铺压实过程.     

面向离散型数控车间的无纸化制造技术研究

在分析企业管理现状的基础上,结合企业信息化应用程度,提出了无纸化制造总体思路,建立了数字化管理模式,搭建了车间数字化制造集成平台,从工艺无纸化、生产管理无纸化、生产物流无纸化及三者之间的信息集成交互进行深入研究,实现产品全生命周期制造过程跟踪,最终形成产品全生命周期制造档案,通过数字化工艺设计、数字化业务管理以及集成生产现场应用,促进企业技术创新和管理提升。