Papers by Keyword: PP

Abstract: The dyeing ability of the polypropylene (PP) fiber was modified by blending with poly(lactic acid) (PLA). The PP, PLA, and PP/PLA fiber were obtained using the melt-spinning technique in the presence of the polypropylene-graft-maleic anhydride as a coupling. The dyeing ability, mechanical and thermal properties, and crystalline structure of the PP, PLA, and PP/PLA fibers were investigated. The effect of dyeing ability was measured using the CIE L^* a^* b^*. The a* value of the PP of 11.91 increased to 43.48 for PP/PLA90, showing a light pink to red color. The SEM images demonstrated smooth fiber with color coating on the fiber. The mechanical property of the fiber indicates that increasing the PLA decreased the tenacity of the PP fiber. The melting behavior of fiber increased with the PLA. The XRD presented the PP's crystalline and the PLA's amorphous structures.

Abstract: The effect of blending polycarbonate (PC) into polypropylene (PP) matrix polymer on thermal conductivity and crystal structure was studied. The blends consisted of 5% to 35% of PC with 5% compatibilizer (polypropylene-graft-maleic anhydride or PP-g-MA), were compounded using twin-screw extruder and shaped into standard tests samples by compression molding. The thermal conductivity values for PP/PC/PP-g-MA blends were ranging from 0.22 – 0.24 W/m.K. When compared to Hanshin – Shtrikman model, the highest difference in the thermal conductivity values was 28.2% shown in 90/5/5 composition. The deviation was due to the exclusion of factors such as PC particulates’ geometry, size, and dispersion in PP matrix. X-ray Diffraction (XRD) test revealed the blends’ structures comprised of medium-range order domains, referring to imperfect crystals with nanoparticles. The locations of peaks in the XRD spectrum also suggest that the pure PP’s monoclinic alpha crystal appeared in all PP/PC/PP-g-MA blends and there was no other crystal obtained in the blends. From the result, the discovered traits of crystal structure displayed influence on the thermal conductivity of the blends. At the same time, reactive compatibilization was suspected to take place at the interface of PP and PC phases when PP-g-MA was introduced.

Abstract: Plastic waste is majority an organic material that cannot easily decomposed by bacteria, so it needs to be recycled. One of the utilization of plastic waste recycling is become a mixture in the manufacture of building materials such as concrete, paving block, tiles, roof. This experiment purpose to find out the effect of addition of variation of LDPE and PP thermoplastic binder to physical and mechanical properties of LDPE/PP/Sand composite for construction material application. In this experiment are using many tests, such are SEM, FTIR, compression strength, density, water absorbability, and hardness. the result after the test are the best composition of composite PP/LDPE/sand is 70/0/30 because its have compression strength 14,2 MPa, while density value was 1.30 g/cm3, for the water absorbability is 0.073%, and for the highest hardness is 62.3 hardness of shore D. From the results obtained, composite material can be classified into construction materials for mortar application S type with average compression strength is 12.4 MPa.

Abstract: In this paper, Sb₂O₃/PP composite specimens were prepared by ball milling and melt blending. The effects of Sb₂O₃ particle size and filling amount on the toughening, reinforcing effect and crystallinity of PP composites were analyzed by notch impact test, tensile test, SEM, XRD and DSC characterization. The experimental results show that the filling of Sb₂O₃ particles can improve the mechanical properties and crystallization properties of Sb₂O₃/PP composites. With the increase of filling amount of Sb₂O₃ particles, the tensile strength and impact strength of Sb₂O₃/PP composite increased first and then decreased. When the content of Sb₂O₃ is 2 wt.%, the tensile strength and impact strength of Sb₂O₃/PP composites reach the maximum. When the filling amount is the same, the crystallization and mechanical properties of nanoSb₂O₃/PP composites are better than those of micron Sb₂O₃/PP composites.

Abstract: This work focuses on studying the possibility of 3D printing of composite materials composed by cork and a polymer matrix (CPC). Initially the cork was mixed with two types of polymers (HDPE and PP) in different proportions and later processed using extrusion and injection. The composites were tested to study the physical, chemical and mechanical properties. The material was then tested on a large-scale 3D printer to study its feasibility and the ability to produce new products through 3D printing. Attention was focused on the use of pure cork, varying the concentration of cork and coupling agent in thermoplastic matrix composites of PP and HDPE. It was demonstrated that the increase of 5wt.% of coupling agent in the two types of polymers significantly improved the mechanical properties and adhesion between the phases but the increase in cork concentration decreased mechanical properties and crystallinity. The CPCs with PP showed to have better mechanical properties, better aesthetic and internal structural quality, and easier processability than those with HDPE matrix. Nevertheless, the HDPE CPCs showed a high degree of crystallization. Concerning 3D printing, with the filament obtained was demonstrated the possibility of making new products based on natural cork fibers, showing promising results, although additional research is still needed to optimize the process.

Abstract: The UV short-wavelength/infrared excitable dual-wavelength fluorescent anti-counterfeiting polypropylene (PP) fibers were spun by the traditional melt spinning process. The effects of pH value, temperature, and solvents on the structure and properties of fibers were investigated by means of tensile tester, fluorescence spectrometer and scanning electron microscope (SEM), respectively. The results showed that the fibers could emit red light under the excitation of 254 nm wavelength UV light and emit green light under the excitation of 980 nm wavelength infrared light, which show the double anti-counterfeiting effects. The dual-wavelength fluorescent fibers showed stable mechanical properties in acid and alkali resistance, whereas the fluorescence properties of fibers decreased with the increase of processing time in acid and alkali solutions. With the extension of high temperature treatment time, the mechanical properties of fibers decreased slightly and tended to be stable, while the fluorescence performance of fibers decreased gradually. The influences of different organic solvents on the properties of fluorescent fibers were different, and the fibers showed relatively good solvent resistance.

Abstract: Green composites shaped by mixture of biodegradable polymers and natural fibers have spellbound massive interest in current years due to their environmentally valuable properties and also to decrease our dependency on the non-renewable resources. Due to the environmental advantages and light weight of natural fibers, an increasing quantity of natural fibers has been used to replace synthetic fibers composites. Coir fiber poly-lactic acid (PLA)/ poly-propylene (PP) resin reinforced polymeric composites have been developed with 90^o orientation. The composition of PLA and PP for resin preparation is taken in the ratio 95:05 whereas for the composite, resins and coir fiber in 80:20. The compression molding technique is applied and then the tests are carried out. Mechanical tests (Impact and Hardness), Micro structural analysis (Fourier Transform Infrared Spectroscopy and Optical Imaging) and Differential Scanning Calorimetry are conducted. According to the investigational verification, the new biodegradable composite shows significant results on par with synthetic/ man made composites and the advantages of using bio-composites has been indicated with simplicity.

Abstract: This paper adopted the mixing modification to prepare MAH-POE/ LMW-EP/PP/CaCO₃ thermoplastic composites, probed into the structure of composites, the system compared the modification made by composites and the single system of the rheological property, the influence law of flow rate, mechanical properties, dynamic mechanical thermal analysis (DMTA) and the network structure of the composite material etc. The results showed that the elastomer was preferably dispersed in the PP, the two phases have a strong interaction force, When the content reaches 20%, the tensile strength decreased by 7.37%, the elongation at break increased by 410.1%, the impact strength reached 546.3J.m², there has been broad and strong low internal friction peak tanδ2 peak, and with the increase of elastomer content, liquidity blends decreases, MFR decreases. In short, quadruple composites have optimum overall performance. Polypropylene (PP) is a source of abundant, excellent mechanical properties, good electrical insulation, and resistance to stress cracking and has good overall performance excellent chemical stability thermoplastics. Widely used in medical equipment, auto parts , building materials, home office supplies, as well as a large number of transport and packaging materials [1-3] . However, due to the strong ability of PP crystallization, resulting PP mold shrinkage, impact toughness is poor [4-5] , in order to solve this problem , the current modification methods often used are: copolymerization and blending modification , and blending is the most simple and effective toughening PP method . The main focus ① blended with a modified rubber or thermoplastic elastomer blends toughening ; ② Toughening with other organic polymers ; ③ rigid inorganic particle toughening ; ④ elastomer / toughening common inorganic particles [6-10] . POE because both thermoplastic plastics , but also the crosslinkable rubber , which has a small cohesive energy , high shear sensitivity , and good compatibility with PP machining , toughening modification of PP the effect is significant and widespread attention , but the larger POE elastomer modified PP viscosity , processing performance be affected [11-13] . In this paper, LMW-EP and MAH-POE-modified PP, while adding CaCO3 prepared by a four-element composite elastomer material, by contrast, explores the compatibility of the quaternary blends, processing fluidity and mechanical properties

Abstract: The aqueous dispersion of MAH-g-PP and KH-550 solution are used in the pretreatment of GF. The effects of pretreatment of the aqueous dispersion of MAH-g-PP and KH-550 solution on the interface crystallization of PP/GF, the suitable temperature and time of the pretreatment of the aqueous dispersion of MAH-g-PP on GF are studied by scanning electron microscope (SEM) and polarized light microscope (PLM). Finally, PLM is used to study the effects of the aqueous dispersion of MAH-g-PP on the crystallization of PP.

Abstract: Polypropylene (PP) and ethylene vinyl acetate copolymer (EVA) were treated with intumescent flame retardants containing caged bicyclic phosphates. The behavior of thermal degradation of the flame-retarded PP and EVA were studied by TG, DSC, and the FTIR spectra of PP’s residues at different temperature were recorded. In addition, the possible thermal degradation and char formation mechanisms were analyzed and discussed.