Morphological Properties Of Polypropylene Research Articles

Effect of UV Aging on the Physical Properties of Polypropylene/Zinc Borate Polymer Composites

Plastics, which have a wide range in terms of production method, have also replaced traditional materials because their chemical and physical properties can be changed in the desired direction. The structural changes that occur when functional filler-additives are used during production cause improvements in many physical properties of the new plastic obtained. The use of boron and boron compounds as additives positively affects the mechanical, thermal, electrical, optical and physical properties of the polymer composite. As it is known, plastics, which are flammable by nature, have a low oxygen index and therefore pose a danger to human life and the environment due to the threat of fire. In this study, the effects of zinc borate, which has flame retardant property, on the physical and morphological properties of polypropylene were investigated. In addition, the effects of aging were investigated by UV aging at 70C for 15 and 30 days on the polymer composites produced in the study. PP/ZnB polymer composites with different concentrations (5, 10, 15, 20%) were produced in a twin screw extruder to provide a more homogeneous mixture. Test samples of polymer composites, which were brought into granule form with the help of a grinder, were successfully molded in the injection machine. Limit oxygen index (LOI) to examine the flaming behavior of the samples, heat deflection temperature (HDT), Vicat softening point, melt flow index (MFI) test to examine the thermal behavior, moisture content and density test to examine the physical properties of the samples were performed. The microstructure examination of polymer composites was made with a scan electron microscope (SEM).

The Effect of Foaming on Mechanical and Morphological Properties of Polypropylene

The automotive industry is among the priority technology areas of our country, and the reduction of vehicle weight and fuel consumption and thus CO2 emissions without compromising safety criteria are among the priority research areas. For this reason, R&D studies on increasing the use of polymer-based materials in the automotive industry are of great importance. In order to produce “high strength and weight reduction parts” in plastic moulding technologies, advanced technologies that focus on cost reduction and efficiency are being implemented rapidly. The chemical foaming process, which provides many advantages such as reducing the consumption of plastic material used, reducing the total moulding cycle time, using less tonnage injection moulding machines, and thus reducing the energy costs, is one of the innovative technologies that have been implemented since a very recent time. In this study, chemical foaming agent were being reinforced at the rate of 1-2-3% in natural fiber-reinforced recycled composite polypropylene raw material. The samples obtained in the injection machine was be moulded in the sizes and shapes in accordance with the standards. Tensile, hardness, impact and three points bending tests would be done. By examining the test results, the mechanical, and morphological properties of natural fiber reinforced polypropylene materials at different chemical agent percentages were examined. With increasing the amount of foaming agent, mechanical properties decreased.

Investigation on the mechanical, thermal, structural and morphological properties of polypropylene/ethylene-vinyl acetate copolymer/graphene oxide nanocomposites: effect of nanofiller surface functionalization and compatibilizers

Rubber toughened PP nanocomposites with desirable thermal properties and tensile strength (TS) found applications in automotive and packaging industries. This article reports on the mechanical, thermal, structural, and morphological properties of polypropylene (PP)/ethylene-vinyl acetate copolymer (EVA) blend reinforced with graphene oxide (GO) and silane-functionalized GO (f-GO). GO was modified with two silanes: γ-glycidoxypropyltrimethoxysilane (GPTMS) and γ-mercaptopropyltrimethoxysilane (MPTMS). The influence of three compatibilizer systems: (PP-g-OH, PP-g-COOH, and PP-g-NH2) on the properties of the composites was also evaluated. The structure and thermal behavior of GO and f-GO were comparatively studied for the first time. The attenuated total reflectance Fourier transform infrared (ATR-FTIR), Raman spectroscopy measurements, and X-ray diffraction (XRD) brought evidence for the successful interactions of silanes with GO. Thermogravimetric analysis (TGA) showed that f-GO exhibited higher thermal stability compared to GO. According to the mechanical analysis, PP/EVA/GPTMS-GO/PP-g-NH2 displayed higher TS and stiffness than the other compatibilized nanocomposites. TGA results indicated that the presence of both f-GO and compatibilizers caused a drastic improvement in the thermal stability. DSC analyses revealed that the addition of nanoparticles led to an increase in PP melting and crystallization temperatures, as well as the degree of crystallinity. XRD patterns revealed the formation of intercalated-delaminated nanocomposites and the promotion of β-phase crystals of PP for the samples containing PP-g-COOH and PP-g-NH2. The scanning electron microscopy (SEM) showed that the addition of compatibilizers drastically reduces the domain size of the EVA particles. All results suggest that GO nanoparticles enhance the mechanical and thermal properties of PP/EVA blend.

Thermal, structural and morphological properties of polypropylene and high density polyethylene polymer composites filled with waste urea formaldehyde

Thermal, structural and morphological properties of polypropylene and high density polyethylene polymer composites filled with waste urea formaldehyde

Property Correlations of Polypropylene based Composites Filled with Mimusop elengi Seed Shell Powder

The saturation point of Mimusop elengi seed shell powder (MESSP) and the effect of MESSP addition on the mechanical, thermal, water absorption and morphological properties of polypropylene (PP) composites were studied. Tensile fracture, physio-mechanical properties and thermal behavior of composites were characterized using tensile and impact testing, thermogravimetric analysis, scanning electron micrograph, and differential scanning calorimetry. Processability of composites were feasible up to 20 wt. % MESSP by which agglomeration of MESSP and poor dispersion of MESSP in PP was observed above 20 wt% MESSP loading. Increasing MESSP loading showed tremendous improvement in tensile modulus and impact strength, whereas tensile strength and elongation at break were reduced. Water absorption and thermal decomposition of composites remain comparable with addition of MESSP up to 20 wt. %. Reduction of tensile strength was attributed by weak adhesion between MESSP and PP. However, morphological analysis revealed the presence of physical interaction via PP chain interlocking on MESSP surface.

Wollastonite and talc reinforced polypropylene hybrid composites: Mechanical, morphological and thermal properties

This study focused on evaluating the mechanical, thermal, and morphological properties of polypropylene (PP) hybrid composites containing two different inorganic mineral fillers, namely wollastonite (WO) and talc. The composites were prepared by melt mixing process using a twin screw extruder and an injection molding machine. All composites contained a constant filler loading at 20 wt% with varying WO/talc weight ratios (20/0, 15/5, 10/10, 5/15, and 0/20). Melt flow index (MFI), mechanical properties (impact strength and tensile properties), heat distortion temperature (HDT) fractured surface morphology, and thermal behaviors of the resulting composites were investigated. The results revealed an enhancement in the MFI, HDT, impact strength, Young’s modulus, crystallization temperature, melting temperature, and degree of crystallinity with a decline in the elongation at break and a small increase in the tensile strength of the composites compared to those of the pure PP. These were according to the lubricating effect (increased flowability), reinforcing effects (increased mechanical properties), barrier properties (increased HDT and melting temperature), and nucleating effect (increased crystallization temperature and crystallinity) of the fillers.

Studies on Thermal and Morphological Properties of Polyurethane Foam Filled Polypropylene/Poly(lactic acid) Blends

Polyurethane foams are used in many different applications, such as insulation and coating materials, packaging, furniture and so on. It has very low weight, low cost and thermal conductivity hereby frequently preferred by architectural and construction industry. On the other hand, these large-scale uses bring with waste problem after applications. In this study, the effect of polyurethane foam waste (PUw) on the thermal and morphological properties of polypropylene (PP)/ poly(lactic acid) (PLA) composites plasticized with polyethylene glycol (PEG 400) was investigated. PUw filled PP/PLA composites were prepared using melt blending followed by compression molding. Thermal and morphological properties of PUw filled PP/PLA composites were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), thermal conductivity analyzer and scanning electron microscopy (SEM). The results shown that the thermal conductivity of the composites improved significantly with addition of PUw, while glass transition temperature (T g ), the melting temperature (T m ) and melting enthalpy (ΔH m ) values of the composites decreased. Based on finding, the PUw could be used as filler in PP/PLA composites for insulation and energy efficiency.

Irradiation effects of Cu ions on the electrical and morphological properties of polypropylene

The irradiation of metallic ions on polymeric surfaces may change the chemical, electrical and physical properties of polymers. In this article, we have investigated the effects on the electrical and morphological properties of polypropylene caused by irradiating with copper (Cu) ions generated from laser-produced plasmas. For this purpose Nd: YAG laser (1064 nm) was employed to produce Cu ions. The flux of ions was controlled by varying the number of laser shots in the range 100–400, with a step size of 100. The changes in the electrical conductivity of the irradiated sample were studied using a four-point probe technique, while the surface features were examined by using optical microscopy. The electrical conductivity changed from 4.758 × 10−8 Ω−1 cm−1 to 5.003 × 10−8 Ω−1 cm−1 for unexposed and exposed (with 400 shots) samples, respectively.

Chemical treatment of cotton stalk and its effects on mechanical, rheological and morphological properties of Polypropylene/cotton stalk bio‐composites

Cotton stalk as commercially viable bio fiber for preparing bio‐composites is explored of late, and the effects of various chemical treatments of cotton stalk fiber on mechanical, rheological and morphological properties of Polypropylene (PP)‐Cotton stalk (CS) bio‐composites are reported in this study. PP‐CS bio‐composites were prepared by varying the amount of cotton stalk from 10 to 50% by melt mixing in twin screw extruder and then injection molded to make specimen. PP‐CS bio‐composites with 50 wt% untreated CS were found to have maximum improvement in tensile modulus (83%), flexural modulus (120%), impact strength (39%). Similar to tensile and flexural modulus, the storage modulus of the PP‐CS composites was also increased with incorporation of CS into the PP matrix. To further increase the interaction between CS and PP matrix, four different chemical treatments (alkali, silane, permanganate solution and stearic acid) were tested for mechanical properties of CS‐PP bio‐composites. Among them KMnO4 treatment was found most effective on overall enhancement of bio‐composite properties. Chemically treated CS‐PP bio‐composites could be an economic viable option to prepare high quality low cost composites for suitable applications in various interior parts of automotives and house hold products. POLYM. COMPOS., 39:E286–E296, 2018. © 2017 Society of Plastics Engineers

Electrical and thermal properties of a thermoplastic elastomer nanocomposite based on polypropylene/ethylene propylene diene monomer/graphene

ABSTRACTThe effect of multilayer graphene (MLG) and few layer graphene (FLG) on electrical, thermal, and morphological properties of polypropylene (PP)/ethylene propylene diene monomer (EPDM) blends prepared by the melt mixing process is reflected in this work. The electrical conductivity test indicates a pronounced increase in electrical conductivity from an insulator to almost a semiconductor with increasing graphene content. The electrical percolation threshold of the prepared nanocomposites was found to be sensitive to the PP/EPDM ratio and type of graphene. The percolation threshold was realized in the concentration range of 0.5–1 wt% of FLG for PP/EPDM (60/40). The power-law model was used to describe the behavior of electrical conductivity of the prepared nanocomposites based on graphene. In this model, the t parameter is dependent on the aspect ratio and dispersion state of graphene. The morphology of the samples was characterized by wide-angle X-ray diffraction (WAXD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) which reveal that the electrical and thermal properties of prepared nanocomposites depend on the aspect ratio, dispersion state of graphene layers, and size of the dispersed phase (EPDM). Thermogravimetric analysis (TGA) of the nanocomposites demonstrates that the maximum thermal degradation and onset thermal degradation were shifted to higher temperatures with the introduction of graphene. The thermal conductivity of the nanocomposites is also remarkably improved with the addition of FLG compared with the nanocomposites based on MLG.

Physical and Mechanical Properties of Polypropylene-Wood-Carbon Fiber Hybrid Composites

Effects of the addition of short carbon fibers (CFs) on the mechanical, physical, and morphological properties of polypropylene (PP) and wood-polypropylene composites (WPCs) were investigated. Hybrid composites (mix of wood and CFs) were manufactured in a two-stage process, pellet extrusion and samples mold injection with varying amounts of poplar wood fiber (0%, 20%, 30%, and 40%) and CFs (0%, 3%, 6%, and 9%), with and without maleic anhydride grafted PP (MAPP) as a coupling agent. The composites were prepared with extrusion blending followed by injection molding. The samples where then tested for mechanical and physical properties, and fractured surfaces where observed with scanning electron microscopy. The results indicated that the addition of CFs to WPCs improved the tensile and flexural strength and the modulus of elasticity but had only a small influence on elongation at break and impact strength. The density of hybrid composites slightly increased with CFs proportion but their water absorption was not affected. Scanning electron micrographs of the tensile fractured specimens showed improved adhesion of CFs and poplar with the PP matrix in the presence of a coupling agent.

The comparison of properties of (rubber tree seed shell flour)‐filled polypropylene and high‐density polyethylene composites

The effect of varied rubber tree seed shell flour (RSSF) filler loadings on processing torque, mechanical, thermal, water absorption, and morphological properties of polypropylene (PP) and high‐density polyethylene (HDPE) composites has been studied. The addition of RSSF in the composites increased the stabilization torque in both PP‐ and HDPE‐based composites. Tensile strength, elongation at break, flexural strength, and impact strength show significant reduction when higher loading of RSSF was incorporated, while tensile modulus and flexural modulus were improved. The phenomenon was noted for both matrices, PP and HDPE, but HDPE‐based composites showed clear effects on the reduction of the mechanical properties compared with RSSF‐filled PP. Scanning electron microscopy of tensile fracture specimens revealed the degree of dispersion of RSSF filler in the matrices. At higher filler loadings, agglomerations and poor dispersion of RSSF particles were spotted, which induce the debonding mechanism of the system. Thermogravimetric analysis thermograms showed that both PP‐ and HDPE‐based composite systems with higher RSSF content have higher thermal stability, initial degradation temperature, degradation temperature, and total weight loss. Water absorption ability of the composites increases as the filler loading increases for both matrices. J. VINYL ADDIT. TECHNOL., 22:91–99, 2016. © 2014 Society of Plastics Engineers

Effects of MWCNT and nickel-coated carbon fiber on the electrical and morphological properties of polypropylene and polyamide 6 blends

In this study, the effects of hybrid fillers such as multi-walled carbon nanotube (MWCNT) and nickelcoated carbon fiber (NCCF) on the electrical conductivity of polypropylene (PP) and polyamide 6 (PA6) blends were investigated. Polypropylene-g-maleic anhydride (PP-g-MAH) was used as a compatibilizer of the PP/PA6 blends. From the results of the transmission electron micrographs of the PP/PA6 (70/30)/MWCNT composites, the MWCNT preferred to locate more in the PA6 phase than in the PP phase. This was possibly due to the lower interfacial tension of the PA6/MWCNT composite compared to that of the PP/MWCNT composite. For the PP/PA6 (70/30)/NCCF/MWCNT (3 phr) hybrid filler composites, values of the electrical conductivities were increased with the increase of the NCCF content. The increase in electrical conductivity was possibly due to the increased electrical pathway with the addition of NCCF content. From the results of the electrical conductivity and morphology of the PP/PA6/NCCF/MWCNT composites, it is suggested that selective localization of the MWCNT in the PA6 phase affected the increased electrical conductivity of the PP/PA6/NCCF/MWCNT composites. The hybrid fillers NCCF and MWCNT could produce a synergistic effect on the electrical conductivity, and the electromagnetic interference shielding efficiency (EMI SE) of the PP/PA6 (70/30)/NCCF/MWCNT composites.

Influence of mesoporous silica and hydroxyapatite nanoparticles on the mechanical and morphological properties of polypropylene

This paper presents the effect of different types of additives on the morphology and mechanical performance of polypropylene (PP). Three different types of nanoparticles, containing mesoporous silica (MCM-41), Hydroxyapatite (HA) and the composite of MCM-41 and HA (MH) were used. Nanocomposites containing PP, 3wt.% of maleic anhydride grafted polypropylene (PP-g-MA) and 3wt.% of different nanoparticles were prepared using the melt-compounding technique in a twin-screw extruder. The bulk mechanical response of the nanocomposites such as tensile, flexural and Izod impact properties were studied. The results of mechanical tests show that at the same nanomaterial content, all the nanofillers cause better tensile, flexural and impact strength than neat PP. The MH nanoparticle improves the mechanical properties of PP, better than the other nanoparticles because this nanofiller contains good properties of both MCM-41 and HA nanoparticles in itself. In order to investigate the effect of foam agent on the mechanical properties of neat PP and nanocomposites based on PP, inorganic azodicarboxamide was added to the aforementioned mixtures as chemical blowing agent and the foamed specimens were resulted using the melt-compounding technique. The results reveal that addition of foam agent to mixtures, leads to increase the flexural characteristics of samples, but the tensile properties and impact strength decrease. Scanning electron microscopy (SEM) was used to assess the fracture surface morphology and the dispersion of the nanoparticles. X ray diffractometry (XRD) was used to examine the intercalation effect on the nanocomposites. The observations show that the nanomaterials were well dispersed in the polymer matrix and the enhancement of the interface between the matrix and fillers was obtained by the incorporation of MH, MCM-41 and HA nanoparticles into PP matrix.

Morphology and Mechanical Properties of PP/LLDPE Blends and Ternary PP/LLDPE/Nano-CaCO3 Composites

Mechanical and morphological properties of polypropylene (PP)/linear low density polyethylene (LLDPE)/ nano-sized calcium carbonate ternary composites were prepared using a twin-screw extruder. Modification of the filler nano-particle surface was pretreated with stearic acid and of the PP/LLDPE interface by melting high crystallizable, high density polyethylene. In this research, effects of modified linear low density polyethylene (LD) and nano-CaCO3 weight percentage on tensile strength, Young’s modulus and impact absorbed energy of composites were investigated. In addition, effect of the interaction between filler particles and polymer matrix was studied. Effect of quantity of microcracks on tensile properties of the composites was also discussed. Effect of nano-CaCO3 and LD on the quantity of microcracks and impact-fractured surface of PP composites was studied by scanning electron microscope (SEM). The impact-fractured surface morphologies were characterized by SEM to clarify the possible mechanisms for improving the fracture resistance.

Mechanical properties of modified biofiller‐polypropylene composites

This article reports the mechanical, thermal, and morphological properties of polypropylene (PP)‐chicken eggshell (ES) composites. Mechanical properties like tensile strength, tensile modulus, izod impact strength, flexural modulus of PP composites with normal (unmodified) eggshell and chemically treated ES [modified ES (MES) with isophthalic acid] have been investigated. PP–calcium carbonate (CaCO3) composites, at the same filler loadings, were also prepared and used as reference. The results showed that PP composites with chemically MES had better mechanical properties compared to the unmodified ES and CaCO3 composites. An increase of about 3–18% in tensile modulus, 4–44% in izod impact strength and 1.5–26% in flexural modulus at different filler loading was observed in MES composites as compared to unmodified ES composites. Scanning electron microscopy (SEM) micrographs of fractured tensile specimens confirmed better interfacial adhesion of MES with polymer matrix resulting into lower voids and plastic deformation resulting in improved mechanicals of the composites. TEM micrographs showed acicular needle shaped morphology for modified ES and have contributed to better dispersion which is the prime reason for enhancement of all the mechanical properties. At higher filler loading, the modulus of MES composite was found to be higher by 5% as compared to commercial CaCO3 composites. POLYM. COMPOS., 35:708–714, 2014. © 2013 Society of Plastics Engineers

Mechanical and Morphological Properties of Polypropylene/Polyoxymethylene Blends

This work studies the mechanical and morphological properties of polypropylene (PP)/polyoxymethylene (POM) blends. The PP/POM blends were prepared by melting-blend with an internal mixer. The contents of PP were used at 10%, 20%, 30%, 70%, 80% and 90% by weight. The phase morphology of the blends was observed by scanning electron microscope (SEM) due to the mechanical properties depended on the phase morphology. The results show the decrease of the impact strength, Young’s modulus and tensile strength of POM/PP blends with increasing of PP content up to 30 wt% and then increase again with a high PP content. The percent strain at break of the blends increases after adding PP in a range of 70 - 90 wt%. SEM study reveals that the POM/PP blends clearly demonstrate a two-phase matrix-particle microstructure. The results also show that the domain size of dispersed PP or POM phase increases with increasing PP or POM content. The POM domain size is smaller than the PP domain size which leads to a little change of mechanical results of PP.

Effects of accelerated aging and compatibilizers on the mechanical and morphological properties of polypropylene and poly(acrylonitrile‐butadiene‐styrene) blends

AbstractThe effects of maleic anhydride‐grafted styrene‐ethylene‐butylene‐styrene copolymer (SEBS‐g‐MAH) on the mechanical and morphological properties of polypropylene (PP) and poly(acrylonitrile‐butadiene‐styrene) (ABS) blends were investigated. Based on mechanical properties, including impact and tensile strengths, the PP/ABS (70/30) blends containing SEBS‐g‐MAH showed improved impact strength with minimal loss of tensile strength. As determined from morphological studies of the PP/ABS blends, addition of SEBS‐g‐MAH decreased PP/ABS blend droplet size more than the addition of SEBS. Additionally, the effects of SEBS‐g‐MAH and SEBS on the mechanical and morphological properties of the PP/ABS (70/30) blends were investigated during accelerated aging in an oven at 90°C for 72 h (one cycle). The impact strength of the PP/ABS (70/30) blends with SEBS‐g‐MAH (7 phr) decreased less than 10% after five cycles, but blends with SEBS (7 phr) and blends without compatibilizer decreased as much as 37%. The tensile strengths of the PP/ABS (70/30) blends after accelerated aging indicated a trend similar to that of the impact strength. The morphological studies indicated no significant changes in the PP/ABS (70/30) blends with SEBS‐g‐MAH; however, many cavities and damages were observed in the blend with SEBS. The above results suggest that SEBS‐g‐MAH acts as an impact modifier and as a good compatibilizer in the PP/ABS (70/30) blends. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Morphological investigation of PP/nanosilica composites containing SEBS

The effect of styrene-(ethylene-co-butylene)-styrene triblock copolymer (SEBS) on the mechanical, thermal and morphological properties of polypropylene (PP) composites filled with nanosilica particles is investigated. A simultaneous increase of all tensile characteristics is observed in PP/nanosilica composites without SEBS and containing 5%SEBS and a large plastic deformation in the nanocomposite with 10%SEBS. Different amounts of β-PP are detected by X-ray diffraction analysis and the calculated K-values correlate well with differential scanning calorimetry results. Quantitative mechanical characterization of nanocomposites is performed at nanolevel, using peak force QNM. This AFM technique allows the detection of nanosilica particles and SEBS domains at the surface of samples and gives indications of local interactions between nanosilica and the matrix from the correlation of modulus and adhesion maps, and the increased local values of elastic modulus on extended areas around nanoparticles.

Polypropylene/Organoclay Nanocomposites: Effects of Clay Content on Properties

The effects of clays as nanoscale fillers have been rarely addressed. Influence of the amount of organoclay (ranging between 1 and 10 wt.%) on the nanocomposites structure, i.e., intercalated or exfoliated, and on the enhancement of mechanical, rheological and morphological properties of polypropylene (PP) nanocomposites was studied in this work. The fundamental material characterization was conducted using XRD, SEM, TEM, DSC, POM, DMTA as well as RMS. Overall mechanical properties determined by tensile tests showed improvements. DSC and POM results demonstrated decrease of nanocomposites crystallinity. XRD and TEM Showed intercalate/exfoliate structures in the resultant nanocomposites.