埃洛石纳米管对PVC/CPE复合材料性能的影响

制备了PVC/CPE/埃洛石纳米管（HNTs）复合材料,研究了HNTs对PVC/CPE复合材料力学性能、微观形貌及热性能的影响.结果显示,HNTs对PVC/CPE材料的增韧效果与基体的韧性及HNTs的添加量有关.当基体韧性较低时,添加少量的HNTs可显著提高PVC/CPE的冲击强度,同时,材料的拉伸强度、弯曲强度和热性能也得到一定的提高.当m（PVC）∶m（CPE）∶m（HNTs）=100∶ 3∶3时,复合材料的冲击强度可达22.17 J/m2,为纯PVC基体树脂的3.4倍,复合材料的冲击断面较粗糙,HNTs在基体中分散较均匀.     

聚丙烯／聚烯烃弹性体共混物非等温结晶动力学及力学性能研究

采用熔融共混法制备了聚丙烯(PP)/乙烯-辛烯弹性体(POE)共混物，在差示扫描量热仪上研究了PP及其共混体系降温过程的非等温结晶动力学，对所得数据分别用Jeziorny法和Mo法进行了处理，表明非等温结晶动力学参数Zc及Avrami指数n随冷却速率的增加而增加；对相同配比的共混物随着结晶度的增加，单位结晶时间里达到一定结晶度所需要的降温速率F(T)增大；当相对结晶度相同时，共混物需要的降温速率减小，所有这些均说明弹性体可作为聚丙烯结晶成核剂。另外，采用偏光显微镜研究了PP及其共混物的结晶形貌，测试了共混物的力学性能。结果表明，弹性体改性的共混物的结晶晶粒明显细化，共混物的冲击强度与断裂伸长率得到明显提高．韧性大幅度提高。     

PEO Coatings Modified with Halloysite Nanotubes: Composition,Properties, and Release Performance

In this work, the properties of the coatings formed on the Mg-Mn-Ce alloy by plasma electrolytic oxidation (PEO) in electrolytes containing halloysite nanotubes (HNTs) were investigated. The incorporation of halloysite nanotubes into the PEO coatings improved their mechanical characteristics, increased thickness, and corrosion resistance. The studied layers reduced corrosion current density by more than two times in comparison with the base PEO layer without HNTs (from 1.1 × 10⁻⁷ A/cm² to 4.9 × 10⁻⁸ A/cm²). The presence of halloysite nanotubes and products of their dihydroxylation that were formed under the PEO conditions had a positive impact on the microhardness of the obtained layers (this parameter increased from 4.5 ± 0.4 GPa to 7.3 ± 0.5 GPa). In comparison with the base PEO layer, coatings containing halloysite nanotubes exhibited sustained release and higher adsorption capacity regarding caffeine.     

Curing Characteristics,Mechanical and Morphological Properties of Kenaf Fibre/Halloysite Nanotubes Hybrid-Filled Natural Rubber Compounds

Natural rubber compounds were prepared with different kenaf/HNT ratio loading i.e., 30/0, 20/10, 15/15, 10/20, 0/30 (phr/phr). The compounds were cured at 150°C according to its t₉₀. Curing characteristic, tensile properties, fatigue, rubber-filler interaction and morphological properties of the compounds were tested. Curing characteristics show that scorch time and cure time increased with increasing of HNT ratio loading while minimum and maximum torque decreased. When HNT ratio loading was increased, tensile strength and elongation at break and fatigue life increased while tensile modulus decreased. Swelling measurement and morphological study showed that better rubber-filler interaction was obtained with higher HNT ratio loading.     

Impact of Filler Functionalisation on the Crystallinity,Thermal Stability and Mechanical Properties of Thermoplastic Elastomer/Carbon Nanotube Nanocomposites

In the present work, the functionalisation of oxidised SWCNTs and MWCNTs is studied. The functionalised fillers are characterised by Raman spectroscopy and TGA. The functionalised fillers are dispersed in a PBT‐PTMO thermoplastic elastomer matrix via in situ polymerisation. The functionalisation causes a fine filler dispersion right at beginning of nanocomposite manufacturing. The fillers act as nucleating agents for crystallisation and evidences for a grafting from PBT at the surface of the functionalised nanotubes are found. An outstanding reinforcement effect by the functionalised CNTs is confirmed by tensile tests.

     

Curing Characteristics,Mechanical, Thermal,and Morphological Properties of Halloysite Nanotubes (HNTs)-Filled Natural Rubber Nanocomposites

Halloysite nanotubes (HNTs)-filled natural rubber (NR) nanocomposites with various filler loading were prepared by using a two-roll mill. The addition of HNTs increased the scorch time, cure time and maximum torque but reduced curing rate index. The tensile strength increased up to 20 phr of HNTs and then decreased. When HNTs loading increased, the elongations of break, swelling percentage and fatigue life were decreased while modulus at 100% and 300% elongation and thermal properties showed inversely. The dispersion of HNTs inside the NR matrix is shown from SEM images.     

PP/POE/WGRT热塑性弹性体的制备及性能研究

采用动态硫化法制备了PP/POE/WGRT共混型热塑性弹性体（TPE）,考察了PP/WGRT共混比、在PP相中填充POE以及动态硫化法对TPE力学性能的影响。结果表明,改变PP/WGRT共混比以及在PP相中填充POE均不能获得TPE;采用动态硫化法制备的PP/POE/WGRT TPE具有较好力学性能,且当DCP用量为3份时TPE力学性能最佳。FE-SEM观察结果表明,动态硫化法使得PP/POE/WGRT TPE的界面作用获得增强,力学性能获得改善。     

Preparation and Properties of Halloysite Nanotubes/Poly(ethylene methyl acrylate)-Based Nanocomposites by Variation of Mixing Methods

Halloysite nanotube-based inorganic–organic polymer nanocomposite has been developed with improved mechanical strength in one direction by solution mixing followed by melt mixing. Melt mixing, solution mixing, and melt-cum-solution mixing were performed to optimize the mechanical strength of the nanocomposites. The field emission scanning electron microscopic images and small-angle X-ray scattering spectrum can support the unidirectional array of halloysite nanotubes in the matrix. The tensile properties revealed that solution–melt mixing is the most desired way to develop clay-based nanocomposites. Thermal characterizations implied that thermal stability was improved after nanoclay incorporation. Dynamic mechanical analysis showed the flow properties and the “Payne effect” of the nanocomposites.     

聚合物/CNTs复合材料制备及其力学性能影响因素

综述了近年CNTs增强聚合物复合材料的制备方法,重点分析了制备过程中影响复合材料力学性能的主要因素,总结了聚合物/CNTs复合材料制备过程中存在的技术难题并对其未来的发展应用进行了展望。     

Tensile,Swelling, and Oxidative Degradation Properties of Crosslinked Polyvinyl Alcohol/Chitosan/Halloysite Nanotube Composites

Glutaraldehyde (GA) crosslinked polyvinyl alcohol (PVA)/chitosan (CS)/halloysite nanotube (HNT) composite films were prepared using a wet casting method. The tensile, morphology, thermal degradation, swelling, moisture, and oxidative degradation properties of crosslinked composite films were carried out. The presences of crosslinking in the composite films were confirmed by FTIR result. The tensile strength of the crosslinked composite films increased up to 0.5 wt% of HNTs loading. Increasing HNTs reduced the thermal degradation, swelling, and moisture properties of crosslinked composite films reduced with the increase of HNTs content. Results also indicated that the crosslinked composite films were degraded using Fenton reagent.     

Mechanical and Morphological Properties of Polypropylene and Regenerated Tire-Rubber Blends

Mechanical properties and morphology of blends prepared from polypropylene (PP) and 5–20 wt% of regenerated tire-rubber (RgR) were studied. The samples were prepared in a twin-screw extruder. The addition of maleic anhydride-functionalized polypropylene (PP-g-MAH) was also investigated. Tensile and flexural moduli, tensile strength at break, elongation at break and Izod impact resistance at 23°C were increased by the addition of 15 wt% of regenerated rubber and 5 wt% of PP-g-MAH. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) analyses showed some interaction between PP and RgR and considerable modification of the compatibilized mixture morphology. The fracture surface of the blend with PP-g-MAH showed a better interaction between the PP matrix and the regenerated rubber domains, for all blends. Well-dispersed particles of the rubber in the polypropylene matrix were observed. DSC showed that PP crystallizes on cooling at lower temperatures as the RgR content increases. The decrease in crystallization temperature is more evident for blends with 5 wt% PP-g-MAH.     

聚丙烯/埃洛石纳米管复合材料的力学及阻燃性能

通过熔融共混的方法制备了聚丙烯/埃洛石纳米管(PP/HNTs)复合材料,并表征了复合材料的力学性能、界面性能和阻燃性能。结果表明,HNTs对阻燃PP发挥进一步阻燃作用,当HNTs含量为2 %时,其极限氧指数可达32.0 %,较阻燃PP提高了2 %;其垂直燃烧性能可达UL 94 V-0级;尤其重要的是,HNTs的加入显著提高了材料的力学性能,含2 %HNTs的复合材料的综合性能最佳,冲击强度为5.4 kJ/m2,拉伸强度为36.5 MPa,弯曲强度为41.4 MPa。     

PVC/MBS/埃洛石纳米管复合材料的制备及其性能

采用熔融共混法制备了聚氯乙烯(PVC)/甲基丙烯酸甲酯-丁二烯-苯乙烯共聚物(MBS)/埃洛石纳米管(HNTs)三元复合材料,研究了HNTs对PVC/MBS共混体系力学性能、热性能和微观结构的影响。结果表明:HNTs与MBS可协同增韧PVC,使复合材料的强度和刚性得到改善,当HNTs的填充量为3 phr时,PVC/MBS(100/3)共混体系的冲击强度、拉伸强度、弯曲强度和弯曲模量分别提高了57.7%、12.1%、7.6%和45.9%;其冲击断面呈现韧性断裂特征;TEM观察结果发现,HNTs在PVC/MBS共混体系中具有良好的分散状态;热失重分析显示,HNTs对PVC/MBS共混体系热稳定性的提高能起到一定作用。     

PP/Rosin Blends: Mechanical and Rheological Properties

Abstract

Melting mixtures of polypropylene (PP) and glycerol ester of hydrogenated rosin (ester gum) were prepared under select conditions using up to 50% of rosin. The addition of modified rosin on PP increased the elastic modulus which maximum value was observed in the 70/30 PP/ROSIN blend. The stress dropped monotonically with rosin content. Above 10% rosin, the elongation at yield diminished and reached a constant value. The elongation at break dropped abruptly above 10% of rosin. The density and hardness of blends increased with amount of rosin. The melt flow index of blends increased exponentially with the rosin content while the torque decreased monotonically with the composition and the processability was improved.     

EPDM/iPB共混型热塑弹性体的制备与性能

通过对比不同共混比的EPDM/iPB共混体系动态硫化与未硫化的力学性能研究发现,动态硫化后的EPDM/iPB体系的性能明显优于未硫化的,当EPDM/iPB的配比为60/40、动态硫化的时间为6min时,综合性能较好;同时,研究了硫化剂和硫化时间等因素对EPDM/iPB力学性能的影响,结果表明:采用DCP/S作为硫化剂、...     

相容剂对PP／PS形态与力学性能的影响

研究了苯乙烯-乙烯／T-烯-苯乙烯共聚物（SEBS）、聚丙烯与苯乙烯接枝共聚物（PP—g-PS）、沙林（Surlyn）对聚丙烯／聚苯乙烯（PP／PS）形态和力学性能的影响。结果表明：SEBS对PP／PS的冲击强度有比较明显的提高，但拉伸强度有所下降；PP-g-PS使PP／PS相界面变得模糊，分散相微粒尺寸变小，分布变窄，PP／PS相容性得到改善；Surlyn使PP／PS力学性能略微下降，增容作用不显著。