Morphological, mechanical, and thermal properties of PP/SEBS/talc composites

2019 ◽  
pp. 089270571987667 ◽  
Author(s):  
Carlos Ivan Ribeiro de Oliveira ◽  
Marisa Cristina Guimarães Rocha ◽  
Joaquim Teixeira de Assis ◽  
Ana Lúcia Nazareth da Silva

The aim of this study is to evaluate the effect of some experimental variables such as the content of styrene–ethylene–butylene–styrene (SEBS) and talc, processing conditions and mixing protocol on the properties of polypropylene (PP). To achieve this objective, PP/SEBS blends and PP/SEBS/talc composites were processed in a corotating twin-screw extruder. A masterbatch of PP/talc was prepared before the extrusion of PP/SEBS/talc composites. The morphology of blends and composites was evaluated by scanning electron microscopy, which revealed the dispersion of small rubber droplets in the PP matrix. Moreover, the micrographs also showed that SEBS and talc particles were uniformly dispersed and distributed in the polymer matrix. Results of thermal properties showed that talc had a nucleating effect, which promoted the increase of both PP crystallization temperature and crystallinity degree. The incorporation of talc in PP/SEBS blends led to an expressive increase in the impact resistance by 70% as compared with the reference blend: PP/SEBS 80/20% (w/w). This result reveals that although the PP/SEBS/talc composites showed a separated morphology, the good dispersion and distribution of this mineral filler in the polymers contributed to avoid crack propagation and increase the impact properties. The tensile properties in the elastic region were not significantly affected.

2019 ◽  
pp. 089270571987822
Author(s):  
Saud Aldajah ◽  
Mohammad Y Al-Haik ◽  
Waseem Siddique ◽  
Mohammad M Kabir ◽  
Yousef Haik

This study reveals the enhancement of mechanical and thermal properties of maleic anhydride-grafted polypropylene (PP- g-MA) with the addition of nanocrystalline cellulose (NCC). A nanocomposite was manufactured by blending various percentages of PP, MA, and NCC nanoparticles by means of a twin-screw extruder. The influence of varying the percentages of NCC on the mechanical and thermal behavior of the nanocomposite was studied by performing three-point bending, nanoindentation, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Fourier-transform infrared (FTIR) spectroscopy tests. The novelty of this study stems on the NCC nanoparticles and their ability to enhance the mechanical and thermal properties of PP. Three-point bending and nanoindentation tests revealed improvement in the mechanical properties in terms of strength, modulus, and hardness of the PP- g-MA nanocomposites as the addition of NCC increased. SEM showed homogeneity between the mixtures which proved the presence of interfacial adhesion between the PP- g-MA incorporated with NCC nanoparticles that was confirmed by the FTIR results. DSC and TGA measurements showed that the thermal stability of the nanocomposites was not compromised due to the addition of the coupling agent and reinforced nanoparticles.


2020 ◽  
Vol 54 (18) ◽  
pp. 2489-2504 ◽  
Author(s):  
Ulas Can ◽  
Cevdet Kaynak

The main purpose of this study was to investigate mechanical and thermal performance of polylactide specimens against UV irradiation; first when only adding benzotriazole benzotriazole-based organic UV absorber (UVA), micro (200 nm) and nano (50 nm) sized titania (TiO2) particles alone, and then to reveal possible synergism when they are added together. Compounds were prepared by twin-screw extruder melt mixing, while the 2 mm thick specimens were shaped by compression molding. Specimens were exposed to UV irradiation under fluorescent lamps (UVB-313) with 0.50 W/m2 for the periods of 12 and 24 days. Changes in the performance of UV irradiated specimens were evaluated in terms of % weight loss, changes in color and chemical structure, including the decreases in the mechanical and thermal properties. Various tests and analysis revealed that synergistic benefits of using micro and nano TiO2 particles together with benzotriazole-type UVA were not only due to the effective stiffening, strengthening and toughening actions of titania particles, but also due to their very significant “UV screening” actions absorbing the photons of the UV irradiation, thus decreasing the degree of the detrimental photodegradation reactions leading to chain scissions in their PLA matrix.


2012 ◽  
Vol 545 ◽  
pp. 330-334
Author(s):  
Sirirat Wacharawichanant ◽  
Pranee Saetun ◽  
Thunwawon Lekkong ◽  
Thongyai Supakanok

This article investigated the effects of particle size of zinc oxide (ZnO) and polystyrene-co-maleic anhydride (SMA) compatibilizer on impact strength and morphology of polystyrene (PS)/ZnO71 (71 nm) and PS/ZnO250 (250 nm) nanocomposites. PS/ZnO nanocomposites with varying concentration of ZnO and SMA were prepared by a melt mixing technique in a twin screw extruder. It was found that the impact strength of PS nanocomposites increased up to a ZnO content of 1.0 wt%. Moreover, PS/ZnO250 nanocomposites had higher impact strength than PS/ZnO71 nanocomposites. The addition of SMA increased the impact strength of PS/ZnO nanocomposites with increasing SMA content. The result showed that SMA could improve impact strength of nanocomposites. The dispersion of ZnO particles on PS/ZnO nanocomposites was studied by scanning electron microscope (SEM). It was observed that the dispersion of ZnO particles of PS/ZnO nanocomposites without SMA was non-uniform and the agglomeration of ZnO particles in the polymer matrix increased with increasing ZnO content. The dispersion of ZnO particles of PS/ZnO nanocomposites after adding SMA was relatively good and only few aggregations exist. These observations support the results of the impact test where the PS/ZnO nanocomposites with SMA displayed higher impact strength than the PS/ZnO nanocomposites without SMA. The study showed that SMA was used as a compatibilizer to improve the dispersability and compatibility of ZnO particles in PS matrix.


2012 ◽  
Vol 527 ◽  
pp. 44-49
Author(s):  
Remo Merijs Meri ◽  
Janis Zicans ◽  
Tatjana Ivanova ◽  
Rita Berzina ◽  
Guntis Japins ◽  
...  

Structure as well as mechanical and thermal properties of the nanocomposites based on recycled polyethylene terephthalate (RPET) are investigated. 1, 2 and 5 wt. % of unmodified montmorillonite nanoclay (MMT) were introduced in the RPET matrix by melt compounding in a twin screw extruder. Results of the investigations testify that optimum content of MMT for modification of RPET is between 1 and 2 wt. %. Up to this nanofiller weight content, the most rapid increase of stiffness, strength and impact toughness is observed. Besides it, at this nanofiller weight content the investigated composite have somewhat improved thermal resistance. It is demonstrated that the improvement of these properties is due to better distribution of MMT in the polymer matrix. At higher nanofiller content, the undesirable effects of the nanofiller agglomeration becomes more important.


Author(s):  
J Li ◽  
Y F Zhang

Polyamide 6 (PA6)-filled polytetrafluoroethylene (PTFE) at different compositions has been successfully prepared in a corotating twin screw extruder where PTFE acts as the polymer matrix and PA6 as the dispersed phase. The morphology and impact properties of these blends were investigated using a scanning electron microscope. The presence of PA6 particles dispersed in the PTFE continuous phase exhibited a coarse morphology. Increasing PA6 contents in the blend improved the impact properties at weak deformation. It was found that the interfacial adhesion played an important role in the creation of an interphase that was formed by the interaction between the PTFE and PA6. This induced an improvement in impact properties. In addition, the optimum impact properties were obtained when the content of PA6 is 30 vol%.


2014 ◽  
Vol 1025-1026 ◽  
pp. 241-245 ◽  
Author(s):  
Ľudmila Dulebová ◽  
Emil Spišák ◽  
Branislav Duleba ◽  
František Greškovič ◽  
Tomasz Garbacz

The paper presents the impact of the use of fillers on the mechanical properties of composites with polymeric matrix from polypropylene (PP). Two main types of mineral fillers - talc and calcium carbonate - were used for experiments. PP composites of different percentage filler in matrix PP were compounded with twin-screw extruder and then injection molding. Properties of composites were investigated by tensile test and thermal analysis. Tensile strength was performed to determine and compare the mechanical properties of the unfilled PP and filled PP with various percentages of fillers. Thermal analysis by thermogravimetric was performed on the tested materials - weight loss, glass transition temperature, thermal decomposition, melting temperature.


2013 ◽  
Vol 4 ◽  
pp. 325-329 ◽  
Author(s):  
Hamonangan Nainggolan ◽  
Saharman Gea ◽  
Emiliano Bilotti ◽  
Ton Peijs ◽  
Sabar D Hutagalung

The effects of the addition of fibres of bacterial cellulose (FBC) to commercial starch of Mater-Bi® have been investigated. FBC produced by cultivating Acetobacter xylinum for 21 days in glucose-based medium were purified by sodium hydroxide 2.5 wt % and sodium hypochlorite 2.5 wt % overnight, consecutively. To obtain water-free BC nanofibres, the pellicles were freeze dried at a pressure of 130 mbar at a cooling rate of 10 °C min−1. Both Mater-Bi and FBC were blended by using a mini twin-screw extruder at 160 °C for 10 min at a rotor speed of 50 rpm. Tensile tests were performed according to ASTM D638 to measure the Young’s modulus, tensile strength and elongation at break. A field emission scanning electron microscope was used to observe the morphology at an accelerating voltage of 10 kV. The crystallinity (T c) and melting temperature (T m) were measured by DSC. Results showed a significant improvement in mechanical and thermal properties in accordance with the addition of FBC into Mater-Bi. FBC is easily incorporated in Mater-Bi matrix and produces homogeneous Mater-Bi/FBC composite. The crystallinity of the Mater-Bi/FBC composites decrease in relation to the increase in the volume fraction of FBC.


2011 ◽  
Vol 45 (26) ◽  
pp. 2811-2816 ◽  
Author(s):  
Yihe Zhang ◽  
Anzhen Zhang ◽  
Zhichao Zhen ◽  
Fengzhu Lv ◽  
Paul K. Chu ◽  
...  

Polypropylene (PP) based composites containing 0, 5, 10, 15, 20, 30, and 50 wt% red mud are granulated by twin-screw extrusion and injection molding. Their mechanical properties such as tensile strength, flexural strength and modulus, impact strength, and thermal properties are determined. After filling with red mud, the flexural strength and modulus, thermal deformation temperature, and Vicat softening temperature increase, whereas the impact strength decreases with increasing red mud contents. The maximum tensile strength is observed from the PP doped with 15 wt% red mud. Scanning electron microscopy (SEM) is used to investigate the dispersion of red mud in the PP matrix.


Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 136
Author(s):  
Edson Antonio dos Santos Filho ◽  
Carlos Bruno Barreto Luna ◽  
Danilo Diniz Siqueira ◽  
Eduardo da Silva Barbosa Ferreira ◽  
Edcleide Maria Araújo

Poly(ethylene-octene) grafted with glycidyl methacrylate (POE-g-GMA) and ethylene elastomeric grafted with glycidyl methacrylate (EE-g-GMA) were used as impact modifiers, aiming for tailoring poly(lactic acid) (PLA) properties. POE-g-GMA and EE-g-GMA was used in a proportion of 5; 7.5 and 10%, considering a good balance of properties for PLA. The PLA/POE-g-GMA and PLA/EE-g-GMA blends were processed in a twin-screw extruder and injection molded. The FTIR spectra indicated interactions between the PLA and the modifiers. The 10% addition of EE-g-GMA and POE-g-GMA promoted significant increases in impact strength, with gains of 108% and 140%, respectively. These acted as heterogeneous nucleating agents in the PLA matrix, generating a higher crystallinity degree for the blends. This impacted to keep the thermal deflection temperature (HDT) and Shore D hardness at the same level as PLA. By thermogravimetry (TG), the blends showed increased thermal stability, suggesting a stabilizing effect of the modifiers POE-g-GMA and EE-g-GMA on the PLA matrix. Scanning electron microscopy (SEM) showed dispersed POE-g-GMA and EE-g-GMA particles, as well as the presence of ligand reinforcing the systems interaction. The PLA properties can be tailored and improved by adding small concentrations of POE-g-GMA and EE-g-GMA. In light of this, new environmentally friendly and semi-biodegradable materials can be manufactured for application in the packaging industry.


2021 ◽  
Vol 5 (9) ◽  
pp. 232
Author(s):  
Samir Kasmi ◽  
Julien Cayuela ◽  
Bertrand De Backer ◽  
Eric Labbé ◽  
Sébastien Alix

The standard polylactic acid (PLA), as a biodegradable thermoplastic polymer, is commonly used in various industrial sectors, food, and medical fields. Unfortunately, it is characterized by a low elongation at break and low impact energy. In this study, a thermoplastic copolyester elastomer (TPCE) was added at different weight ratios to improve the impact resistance of PLA. DSC analysis revealed that the two polymers were immiscible. A good balance of impact resistance and rigidity was reached using the formulation that was composed of 80% PLA and 20% TPCE, with an elongation at break of 155% compared to 4% for neat PLA. This new formulation was selected to be tested in a fused filament fabrication process. The influence of the nozzle and bed temperatures as printing parameters on the mechanical and thermal properties was explored. Better impact resistance was observed with the increase in the two thermal printing parameters. The crystallinity degree was not influenced by the variation in the nozzle temperature. However, it was increased at higher bed temperatures. Tomographic observations showed an anisotropic distribution of the porosity, where it was mostly present between the adjacent printed filaments and it was reduced with the increase in the nozzle and bed temperatures.


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