Polymer-Modified Bitumen Using Ethylene Terpolymers

Polymer modified bitumen (PMB) is used in various construction applications, especially in motorways. The aim of this study is to improve features of 60/70 penetration grade, modified bitumen used on highways. Increasing the sensitivity to temperature and oxidation resistance are very important points for the modified bitumen. This condition was provided by reacting the carboxylic acid groups in asphaltene with the reactive ethylene terpolymer to form ester. Reactive ethylene terpolymer (RETP) and ethylene terpolymer (ETP) manufactured by DuPont USA were used as additives in this study. Infrared Spectrophotometer (IR) graphics and optical pictures of the modified bitumen have been examined. It has been observed that the softening point has increased on the other hand, the penetration and ductility values have decreased according to the test results.     

Surface tailoring of an ethylene propylene diene elastomeric terpolymer via plasma‐polymerized coating of tetramethyldisiloxane

In the research presented here, we explore the use of a low‐energy plasma to deposit thin silicone polymer films using tetramethyldisiloxane (TMDSO) (H(CH₃)₂? Si? O? Si? (CH₃)₂H) on the surface of an ethylene propylene diene elastomeric terpolymer (EPDM) in order to enhance the surface hydrophobicity, lower the surface energy and improve the degradation/wear characteristics. The processing conditions were varied over a wide range of treatment times and discharge powers to control the physical characteristics, thickness, morphology and chemical structure of the plasma polymer films. Scanning electron microscopy (SEM) shows that pore‐free homogeneous plasma polymer thin films of granular microstructure composed of small grains are formed and that the morphology of the granular structure depends on the plasma processing conditions, such as plasma power and time of deposition. The thicknesses of the coatings were determined using SEM, which confirmed that the thicknesses of the deposited plasma‐polymer films could be precisely controlled by the plasma parameters. The kinetics of plasma‐polymer film deposition were also evaluated. Contact angle measurements of different solvent droplets on the coatings were used to calculate the surface energies of the coatings. These coatings appeared to be hydrophobic and had low surface energies. X‐ray photoelectron spectroscopy (XPS) and photoacoustic Fourier‐transform infrared (PA‐FT‐IR) spectroscopy were used to investigate the detailed chemical structures of the deposited films. The optimum plasma processing conditions to achieve the desired thin plasma polymer coatings are discussed in the light of the chemistry that takes place at the interfaces. Copyright © 2004 Society of Chemical Industry     

含活性硅氧烷型大分子改性剂BA-MMA-VTES的合成与表征

针对弱极性天然/丁苯橡胶复合体系,从分子设计的角度出发,选择乙烯基三乙氧基硅氧烷(VTES)、丙烯酸丁酯(BA)、甲基丙烯酸甲酯(MMA)为单体,通过自由基溶液聚合并优化了反应条件:在85℃和115℃分别加入两种不同量的引发剂BPO和DCP,均保温反应2h,合成了三元共聚物BA-MMA-VTES大分子表面改性剂,用于纳米碳化硅、氮化硅陶瓷粉体的表面改性。采用FTIR、NMR、GPC、DSC、TGA等对所合成的三元共聚物的结构、性质和数均相对分子质量进行了分析和表征。通过FTIR、NMR测试结果,证实了BA-MMA-VTES三元共聚物的结构;通过GPC测试,证明BA-MMA-VTES三元共聚物的数均相对分子质量控制在3000～10000;DSC显示合成的大分子只有一个Tg,在3.3℃左右,表明它是无规共聚物,柔性适中;TGA显示三元共聚物主要热分解区间在280～500℃,热稳定性良好。     

动态三螺杆挤出机制备热塑性硫化胶的研究

对比分析了动态热塑性硫化胶(TPV)的加工设备,着重介绍了附加振动力场的三螺杆反应挤出机的结构特点以及利用该机进行三元乙丙橡胶/聚丙烯(EPDM/PP)的动态全硫化,对制品的物理力学性能和微观结构分别进行了测试分析和电镜扫描。结果表明,振动力场作用下EPDM/PP共混体系反应挤出动态硫化加工可有效地实现动态硫化反应、硫化橡胶的粉碎和分散以及相态反转,振动力场的作用明显提高了TPV性能。     

Blends of ethylene–methyl acrylate–acrylic acid terpolymers with ethylene–acrylic acid copolymers: Mechanical and thermomechanical properties

The effect of methyl acrylate content in ethylene–methyl acrylate–acrylic acid (E–MA–AA) terpolymers and acrylic acid content in ethylene–acrylic acid (E–AA) copolymers was investigated in blends of these two materials. The E–MA–AA terpolymer with 8 mol % methyl acrylate was not miscible with any E–AA material no matter what the AA content, whereas the terpolymer with only about 2 mol % methyl acrylate was miscible, at least to some extent, with the E–AA copolymer at high acrylic acid contents. Evidence supporting this conclusion derived from gloss, differential scanning calorimetry testing, and dynamic mechanical measurements. For the E–AA polymer material with the highest acid content, there was a synergistic effect for some properties at low added amounts of E–MA–AA copolymer; the tensile strength and hardness were 10% higher than values for the E–AA copolymer, even though the E–AA copolymer was much stiffer. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2216–2222, 2004     

Effects of ultrasonic oscillation on processing behaviors of PS,EPDM, and PS/EPDM blend

In this study, the extrusion processing behaviors of polystyrene (PS), ethylene–propylene–diene terpolymer (EPDM), and their blend (PS/EPDM, 80/20) were studied by using a special ultrasonic oscillation extrusion system developed in our laboratory. The die pressure and volume flow rate were measured at different ultrasonic intensities and screw rotation speeds. The dependences on ultrasonic intensity of die pressure, volume flow rate, and apparent viscosity of polymers, as well as die swell at the same screw rotation speed were investigated. The effects of screw rotation speed on the processing behaviors of polymers and their blend at the same ultrasonic intensity were also studied. The experimental results showed that in the presence of ultrasonic irradiation, the processibilities of polymers and their blend were improved. Their possible mechanism is discussed in this article. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 1856–1863, 2006     

Compatibilisation of PPE/SAN blends by triblock terpolymers: Correlation between block terpolymer composition, morphology and properties

Immiscible blends of poly(2,6-dimethyl-1,4-phenylene ether) (PPE) and poly(styrene-co-acrylonitrile) (SAN) with a weight composition of 60/40 were compatibilised by polystyrene-block-polybutadiene-block-poly(methyl methacrylate) triblock terpolymers (SBM) using a two-stage melt-processing approach. In order to investigate the influence of the SBM composition on the compatibilisation efficiency, the block lengths of the triblock terpolymers were systematically varied. The resulting morphological features of the blend systems as function of SBM composition and processing parameters are correlated with the resulting thermal and thermo-mechanical properties. In the ideal case, SBM should be located at the interface as PS is miscible with PPE while PMMA is miscible with SAN. The elastomeric middle block as an immiscible component should remain at the interface. This particular morphological arrangement is known as the ‘raspberry morphology’. A detailed TEM analysis of the blend morphologies following initial extrusion-compounding revealed a high compatibilisation efficiency of the SBM types with equal lengths of the end blocks and, furthermore, the desired raspberry morphology was achieved. In contrast, high PS contents in comparison to the other blocks led to a pronounced micelle formation in the PPE phase. Further evaluation of the blend structures following injection-moulding indicated that the morphologies remain relatively stable during this second melt-processing step. A detailed thermal analysis of all blend systems supports the interpretation of the observed morphological features. The fundamental correlation between SBM composition and blend morphology established in this study opens the door for the controlled development of interfacial properties of such compatibilised PPE/SAN blends during melt-processing.     

Regulation of Polymer Configurations Enables Green Solvent-Processed Large-Area Binary All-Polymer Solar Cells With Breakthrough Performance and High Efficiency Stretchability Factor

With the great potential of the all-polymer solar cells for large-area wearable devices, both large-area device efficiency and mechanical flexibility are very critical but attract limited attention. In this work, from the perspective of the polymer configurations, two types of terpolymer acceptors PYTX-A and PYTX-B (X = Cl or H) are developed. The configuration difference caused by the replacement of non-conjugated units results in distinct photovoltaic performance and mechanical flexibility. Benefiting from a good match between the intrinsically slow film-forming of the active materials and the technically slow film-forming of the blade-coating process, the toluene-processed large-area (1.21 cm²) binary device achieves a record efficiency of 14.70%. More importantly, a new parameter of efficiency stretchability factor (ESF) is proposed for the first time to comprehensively evaluate the overall device performance. PM6:PYTCl-A and PM6:PYTCl-B yield significantly higher ESF than PM6:PY-IT. Further blending with non-conjugated polymer donor PM6-A, the best ESF of 3.12% is achieved for PM6-A:PYTCl-A, which is among the highest comprehensive performances.     

AMV降凝剂分子结构的Monte Carlo模拟优化研究

针对降凝剂分子结构的设计和优化问题,本文运用Monte Carlo模型模拟研究了丙烯酸十八酯-马来酸酐-醋酸乙烯酯三元共聚物（AnMmVp）同原油蜡烃组分间的相容性。以理论计算结果为依据指导合成了AMV共聚物降凝剂,并进行了红外表征和实验验证,实验结果表明,当亲油基团（丙烯酸十八酯,AA18）与极性基团（马来酸酐-醋酸乙烯酯,MA—VA）摩尔比为8：2时,二者混合能最低,原油对A8M1V1降凝剂感受性最佳,凝点降低值达8℃,是理想的原油降凝剂结构,这与理论计算结果基本一致。该研究为原油降凝剂分子结构的设计和优化提供了有效涂释。     

Designing block copolymer architectures for targeted membrane performance

Using a combination of block copolymer self-assembly and non-solvent induced phase separation, isoporous ultrafiltration membranes were fabricated from four poly(isoprene-b-styrene-b-4-vinylpyridine) triblock terpolymers with similar block volume fractions but varying in total molar mass from 43 kg/mol to 115 kg/mol to systematically study the effect of polymer size on membrane structure. Small-angle X-ray scattering was used to probe terpolymer solution structure in the dope. All four triblocks displayed solution scattering patterns consistent with a body-centered cubic morphology. After membrane formation, structures were characterized using a combination of scanning electron microscopy and filtration performance tests. Membrane pore densities that ranged from 4.53 × 10¹⁴ to 1.48 × 10¹⁵ pores/m² were observed, which are the highest pore densities yet reported for membranes using self-assembly and non-solvent induced phase separation. Hydraulic permeabilities ranging from 24 to 850 L m⁻² h⁻¹ bar⁻¹ and pore diameters ranging from 7 to 36 nm were determined from permeation and rejection experiments. Both the hydraulic permeability and pore size increased with increasing molar mass of the parent terpolymer. The combination of polymer characterization and membrane transport tests described here demonstrates the ability to rationally design macromolecular structures to target specific performance characteristics in block copolymer derived ultrafiltration membranes.