PP/SBS/EVA三元共混改性制备汔车仪表板专用料的研究

聚丙烯(PP)由于具有价格低、原材料丰富、力学均衡性好、耐化学腐蚀等特点,近年来成为最热门的汽车零部件材料.本文以聚丙烯为基体树脂,热塑性丁苯橡胶(SBS)为主增韧剂,乙烯/醋酸乙烯共聚物(EVA)为辅助增韧剂,通过三元共混改性制备汽车仪表板专用料,并对改性的聚丙烯的材料的冲击强度、弯曲强度、弯曲模量、拉伸强度、断裂伸长率、收缩率、熔体流动速率进行测试.应用正交设计,确定了制备汽车仪表板专用料最佳配方.     

载货车内饰护板用改性聚丙烯专用料研究

利用双螺杆挤出机,通过熔融共混工艺制备了载货车内饰护板改性聚丙烯(PP)专用材料,并对专用料进行了力学性能测试.研究结果表明.以共聚PP为基体树脂、聚烯烃弹性体(POE)为增韧剂、滑石粒为填料制备的载货车内饰护板专用料·其缺口冲击强度达到18.6 kJ/m2,弯曲强度为30.2 MPa.拉伸强度达24.2 MPa,能满足载货车内饰护板类零部件的性能要求.     

高流动性、高刚性、耐冲击汽车保险杠专用料的研制

研究了不同增韧剂、填料、润滑剂、偶联剂及其用量对汽车保险杠专用料性能的影响。结果表明,以聚丙烯(7760)为基体树脂,聚烯烃弹性体(8003)为增韧剂,滑石粉为填料制备的保险杠专用料,其悬臂梁缺口冲击强度达到40 kJ/m2,弯曲弹性模量为1.46 GPa,拉伸强度为19.8 MPa,达到汽车保险杠专用料的性能指标,可替代同类进口产品。     

小型家电专用料的研制

利用双螺杆挤出机，通过熔融共混工艺制备了改性聚丙烯（PP）小家电专用料，研究了聚烯烃弹性体POE和无机复合矿粉的添加量对共混体系性能的影响。研究结果表明：以均聚PP为基体树脂、质量分数10％POE为增韧剂、质量分数25％经活化处理的无机复合矿粉为增强剂制备的改性聚丙烯（PP）专用料，其性能可满足小家电专用料要求。     

中华A1-下护板改性PP专用料的研制及应用

探讨了采用双螺杆挤出机生产中华A1-下护板改性聚丙烯(PP)专用料的配方和工艺,分析了增强剂玻璃纤维、增韧剂(乙烯/辛烯)共聚物(POE)和偶联剂对改性PP材料拉伸强度、缺口冲击强度、弯曲弹性模量、耐热性等性能的影响,选择了最佳的下护板专用料配方。采用新研制的下护板改性PP专用料生产的下护板可满足中华A1-下护板的使用要求。     

聚丙烯冰箱抽屉专用料的研制

研究了以聚丙烯（PP）为基础树脂，以POE为增韧剂，同时加入无机填料制备冰箱抽屉用改性PP共混物的方法，并讨论了共混物组成，用量及共混物形态结构对专用料性能的影响。     

小本体聚丙烯共混改性的研究与应用

以小本体聚丙烯（PP）为基料，通过与共聚丙烯（CPP），聚烯烃弹性体（POE），硅灰石（滑石粉）以及其它助剂共混改性制备汽车专用料。分析检测表明，滑石粉的增强效果好，而硅灰石在增强的同时有增韧功能，共混料完全可以满足汽车专用料的性能要求。     

改性聚丙烯板框专用料研究

从共混改性的角度探讨了用改性聚丙烯生产的板框专用料的耐热性及物理性能。考察了板框专用材料的抗老化性能，冲击强度，为形温度，弯曲强度，熔体流动速率，拉伸强度，等。开发的板框专用料的性能超过了进口料的性能，大幅度降低了原料，取产好的效果。     

我国改性聚丙烯汽车专用料的开发现状及前景

综述了我国改性聚丙烯（ＰＰ）汽车专用料的性能和研究应用情况，并探讨了改性ＰＰ汽车专用料今后的发展前景     

夏利汽车内饰件专用料的研制

采用双螺杆挤出加工，通过添加不同组分的改性助剂，制得夏利汽车聚丙烯内饰件专用料。对聚丙烯专用材料的综合性能进行了测评；并比较了聚丙烯品种、增韧剂、填充材料及聚乙烯对内饰件材料的改性效果；分析了生产工艺对材料性能的影响。据此确定了材料的最佳工艺参数和配方，并成功应用于夏利汽车内饰件。     

Assessment of the Thermodynamic Values for PuO1.5 and High-Temperature Determination of the Values for PuC1.5

Thermodynamic values for PUO_1.5 were assessed using an improved method for estimating fef ° 1.5 and new data for S°₂₉₈ 1.5. Based on the assessment, a value of ΔH°₂₉₈, 1.5=–828 kJ/mol is recommended. Measurements of (CO) pressure over the nominal equilibrium 1.5+ 1.5+ C were performed between 1348 and 1923 K, yielding pressures between 0.644 and 11600 Pa. Second- and third-law analyses were used to obtain a value for ΔH°₂₉₈ 1.5=–93.3°3.3 kJ/mol.     

Experimental Evidence for the Existence of the Ti3B4 Phase

Experimental evidence for the formation of Ti₃B₄ with an orthorhombic Ta₃B₄-type structure is presented. This phase forms by a peritectic reaction between TiB₂ and liquid at ∼2200°C and is stable to temperatures at least as low as 1690°C, the lowest temperature at which samples were annealed. No evidence was found to indicate the presence of a second high-temperature form of this phase, as has been reported in the literature.     

Different approach for the correlation of the Tg of mixed amorphous systems

An empirical equation relating the glass transition (measured dynamically) of mixed systems to their pure components T_gs can be fitted by the following relationship:

$\text{In}\text{T}{}_{\mathrm{g}}\text{=m}{}_1\text{In}\text{T}{}_{\mathrm{g1}}\text{+ m}{}_2\text{In}\text{T}{}_{\mathrm{g2}}$

where m is either volume or wt % of each component. The thermodynamic implications of the logarithmic relationship have been considered and it is shown that other relationships governing the T_g of mixed systems (Fox equation etc.) can be derived using certain thermodynamic constraints. A general power law dependence of log T_g on the apparent activation energy of T_g at a given frequency is also ascertained from experimental data and it is shown that this power law relationship can be obtained from the WLF approach to the glass transition. From this, a relationship concerning the apparent activation energies of T_g (at a fixed frequency) of a mixed system as a function of the pure component activation energies is derived.     

Mechanism for the formation of PNIPAM/PS core/shell particles

A multi‐stage polymerization method was previously used to prepare PNIPAM/PS core/shell particles that exhibited uniform “raspberry‐like” structures. In this current study, this polymerization process was carefully investigated in order to elucidate the PS (polystyrene) shell formation mechanism. The results indicated that the “raspberry” structure is due to heterocoagulation of polystyrene domains onto PNIPAM (poly(N‐isopropylacrylamide)) particle surfaces. Different sizes and numbers of the PS domains can be obtained by varying the styrene feed rate. It was also found that linear PNIPAM may increase the compatibility between PNIPAM and PS polymers. In addition, this heterocoagulation mechanism for forming structured particles was successfully applied to a PNIPAM and Ludox^® colloidal silica nanoparticle system where a core/shell structure was also obtained. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40124.     

Alternatives for the Purification of the Blend Butanol/Ethanol from an Acetone/Butanol/Ethanol Fermentation Effluent

Biobutanol is a biofuel with potential to substitute gasoline. It can be generated through fermentation of lignocellulosic material, by which acetone, butanol, and ethanol (ABE) are obtained and subsequently separated. Nevertheless, the blend ethanol/butanol itself is a fuel, so its separation could be not even necessary. An alternative is proposed to simplify the purification step of the ABE mixture, avoiding the separation of the ethanol/butanol blend. Intensification alternatives are suggested for the resulting structure. The proposed schemes are optimized through a stochastic approach, minimizing the total annual cost and the eco‐indicator 99. The individual risk index is computed for selected designs. The suggested designs reduce the individual risk index by around 30–66 %.     

Combustion modifications for the control of NOx emissions

A theoretical evaluation of combustion modification techniques for the control of nitric oxide emissions from radiant dominated industrial and utility     

RAFT/MADIX polymers for the preparation of polymer/inorganic nanohybrids

Organic–inorganic hybrid nanocomposites are an emerging class of materials that hold significant promise due to their outstanding properties, which usually arise from a combined and/or synergistic effect of the properties of their organic and inorganic components. Despite the numerous functionalization methods described in literature, only a few of them allow precise and easy control of the chemical composition and structure of the organic shell, whereas this point is critical to control some of the nanohybrids properties such as solubility, specific interaction and so forth. In this context, reversible addition-fragmentation chain transfer polymerization/macromolecular design by interchange of xanthates (RAFT/MADIX) technology is a fantastic tool that can be easily performed in mild and “green” conditions, being compatible with a huge variety of functional monomers and providing an excellent control of the organic shell characteristics. This review aims to describe the state of the art of the use of RAFT/MADIX polymers for the preparation of these nanohybrids. After describing the most commonly used synthetic strategies for nanohybrids preparation, the main families of polymers are discussed in view of their chemical composition (homopolymer, copolymer, …) and/or the targeted properties (hydrophilic, hydrophobic, stimuli-responsive). The main advantages of RAFT/MADIX technology are discussed in terms of the numerous applications of those materials.     

Thermodynamic Analysis of the Metastable Regions for the AI2O3-SiO2 System

The paper offers a short review of investigations conducted on the Al₂O₃-SiO₂ system, particularly from the point of view of an appearance of immiscibility gaps, below the liquidus temperatures. Based on theoretical criteria and using the data along the liquidus curves (for mullite and corundum), this investigation suggests immiscibility regions at both ends of the phase diagram. That is, it defines the Margules polynomials for calculation of the activity coefficients necessary for determining the Gibbs energy of mixing. Obtained results are in good agreement with the results reported by Risbud and Pask and other investigators who have found immiscibility gaps at rather high temperatures.     

MgO-modified VOx/SBA-15 as catalysts for the oxidative dehydrogenation of n-butane

VO_x catalysts supported on SBA-15 with and without MgO modification were prepared and characterized by N₂ adsorption–desorption, XRD, HRTEM, H₂-TPR, NH₃-TPD and XPS. Compared to the VO_x/SBA-15 catalyst, the VO_x/MgO/SBA-15 ones exhibit much higher C₄-olefins selectivity and yield in the oxidative dehydrogenation of n-butane. The enhanced performance can be attributed to the rise in VO_x reducibility as well as to the relatively lower acidity of the MgO-modified SBA-15 materials.