• Composites Research
• /
• v.26 no.3
• /
• pp.170-174
• /
• 2013

Atmospheric glow plasma polymerization was applied to wood powder before fabricating polypropylene (PP) matrix composites. Seven different types of monomers (Oxygen, Benzene, CH4, Acrylic-acid, Hexafluoroethane, Trifluorotolune, Hexamethyl-disiloxane) were analyzed to determine the most suitable precursor for plasma polymerization. The surface energy was calculated from measured contact angle about each monomer on PP. Hexamethyl-disiloxane (HMDSO) had a highest surface energy and is selected as the most suitable monomer. Wood powder and polypropylene were mixed as pellets by twin screw extruder and then 50 wt% wood powder/PP composites were produced by an injection machine. Tensile strength and Flexural strength have improved by 7.59% and 12.43% at the maximum respectively. SEM (Scanning Electron Microscope) observation on the fracture surface revealed that the plasma polymerization have improved the interfacial bonding and the mechanical properties of the composites.

• Elastomers and Composites
• /
• v.52 no.1
• /
• pp.35-47
• /
• 2017

A comprehensive survey of the available literature showed that in the last few decades, there has been a growing interest in the use of thermoplastic vulcanizates (TPVs). TPVs are the second largest group of soft thermoplastic elastomers (TPEs) after styrene-based block copolymers, and offer a wide range of potential and proven applications, including in mechanical rubber goods, under-the-hood applications in the automotive field, industrial hose applications, electrical applications, consumer goods, and soft touch applications. Over the last two decades, TPVs have shown a strong and steady market growth (~12% per year). Commercialized TPVs are commonly based on blends of ethylene propylene diene monomer (EPDM) rubber and polypropylene (PP), and to a lesser extent on combinations of butyl or nitrile rubber with PP. EPDM/PP TPVs are characterized by finely dispersed crosslinked EPDM rubber particles (particles size varying between 0.5 and $2.0{\mu}m$) distributed in a continuous thermoplastic PP matrix. If the rubber particles of such a blend are small enough and if they are vulcanized well enough, then the properties of the blend are generally improved. This review article introduces various topics and aspects relevant to EPDM/PP TPVs. The development of TPVs, the use of various types of crosslinking systems and co-agents as crosslinking agents for PP/EPDM blends, the morphology and rheology of TPVs, and their typical end-use applications are also reviewed.

• Clean Technology
• /
• v.5 no.2
• /
• pp.45-52
• /
• 1999

Recycling of red mud from the aluminium manufacturing process was investigated to be utilized as plastic fillers. High density polyethylene(HDPE), low density polyethylene(LDPE) and polypropylene(PP) were found to be the suitable plastic material for which red mud can be used as fillers. With the addition of red mud the plastic showed red brown color. As the ratio of amount of red mud to plastic increased, the tensile strength increased while the Izod impact strength decreased. About five percent of ethylene vinyl alcohol(EVA) was needed as an additive to prevent the lowering of impact strength. Maleic anhydride modified polypropylene was effective for reduction of impact strength lowering of PP. Mixed waste plastics containing LDPE, HDPE, PP, polystyrene and ABS could also accommodate red mud as fillers. In this case, significant loss in mechanical properties were observed due to immiscibility between the components. Ethylene propylene rubber(EPR) and styrene butadiene styrene block copolymer (SBS) could be used to improve the impact properties of the commingled waste plastics.

• Journal of the Korean Society of Safety
• /
• v.16 no.1
• /
• pp.43-47
• /
• 2001

Effect of coupling agent on the mechanical properties of PP/GF blend was investigated. The flexural modulus, Izod impact strength, elongation at yield and tensile strength were improved with using coupling agent. Mopological studies revealed that PP and GF were incompatible and addition of coupling agent was very effective to enhance the compatibility, result in mechanical properties.

• Proceedings of the Korean Fiber Society Conference
• /
• 1998.10a
• /
• pp.240-243
• /
• 1998

범용 수지로서 널리 사용되고 있는 폴리프로필렌(polypropylene, PP)은 결정성 열가소성 폴리올레핀으로 상업적으로는 1957년에 최초로 생산되어졌다. 한편, ethylene-propylene-diene terpolymer(EPDM)는 1963년에 시판된 이래 내구성, 절연성, 화학적 저항성 등 우수한 성질을 가지고 있는 재료로 알려져 있으며, 특히 PP의 저온 내충격성을 향상하기 위해서 주로 사용되었다. (중략)

• Electrical & Electronic Materials
• /
• v.9 no.10
• /
• pp.1033-1039
• /
• 1996

Electrical and mechanical properties of polymer sheet at cryogenic temperature have been investigated. Tensile stress(and strain at break) in liquid nitrogen(77K) of 79.7MPa(l.2%) and 117.4MPa(2.05%) are evaluated for films of Polypropylene (PP) and Kapton, respectively. Dielectric loss tangent(tan .delta.) of PP and Kapton films is almost independent of the frequency and tensile stress. Also, field strength of PP film at 77K decreases with increasing the tensile stress.

• Korean Journal of Food Science and Technology
• /
• v.31 no.1
• /
• pp.158-163
• /
• 1999

The quality change of black rice during storage at $20^{\circ}C$ was measured to determine a packaging material for black rice storage, using polyethylene film (PE), polypropylene film (PP) and laminated film with PE and PP (PE/PP). Water activity of black rice was 0.642 at initial time and changed little in 8 months during storage at $20^{\circ}C$. Acidity of black rice was 25 mg KOH at initial time and was the lowest, 33.16 mg KOH, within PE/PP of 0.10 mm in thickness in 8 months during storage at $20^{\circ}C$. L, a and b values, hunter color value of black rice were not changed significantly in all packaging materials during 8 month storage. Hardness of the black rice was increased a little, but changed the smallest in PF/PP and the largest in PE with 0.05mm in thickness in 8 months. During storage, hexanal content was increased the smallest in PE/PP and the largest in 0.05 mm PE. Among fatty acid of black rice, linoleic acid was changed the smallest in PE/PP and the largest in 0.05 mm PE. In conclusion, PE/PP was better for the storage of black rice than PE and PP.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.15 no.6
• /
• pp.4039-4045
• /
• 2014

The crystallization behavior of irradiated polypropylene (PP) and the blend is an important parameter for polymer processing. Blends of PP/low density polyethylene (LDPE) with different LDPE contents were prepared by melt mixing in a twin screw extruder. The effect of the LDPE content on the irradiation effectiveness of the PP/LDPE blend with trimethylolpropane-trimetacrylate (TMPTMA) as a crosslinking co-agent was investigated in conjunction with the LDPE loading in the blend. The non-isothermal crystallization and crystal structure were measured by DSC, X-ray diffraction (XRD), and polarized optical microscopy (POM). A decrease in the melting temperature of PP was observed due to irradiation, which may be due to the PP chain scissioning effect of irradiation. The Ozawa component n represents a rod shaped, disc shaped and sphere-shaped geometry of the crystal if the value corresponds to 2, 3 and 4, respectively. Based on Ozawa analysis, the values of n were 3.8 and 2.3 for the pure PP and PP blends with 30 wt% LDPE, respectively. The fact that the crystal geometry of PP changed from spherical to disc and rod shaped was confirmed by Ozawa analysis and POM. The ${\beta}$ form XRD peak of the PP/LDPE blend at $16.1^{\circ}$ disappeared after irradiation due to the crosslinking reaction.

• Science of Emotion and Sensibility
• /
• v.14 no.1
• /
• pp.117-126
• /
• 2011

This study investigates the physical properties and manufacturing method of shape memory fabric for emotional garment made by polypropylene. For this purpose, polypropylene(PP) POY and SDY were texturized using low temperature and constant length heat treatment texturing technologies, respectively. The shape memory fabrics made using these texturized PP yarns were woven with two kinds of PET and PTT shape memory yarns on the air-jet loom and the various physical properties of four kinds of shape memory fabrics were measured and discussed. The tenacity and breaking strain of PP texturized yarns treated by low temperature and constant length heat treatment showed high weaving efficiency and the wet thermal shrinkage of PP textured yarns was shown less than 1.5%, dry thermal shrinkage was ranged between 3% and 5%, which means thermal stability compared to the PTT textured yarn with high thermal shrinkage, 5~8%. The shape memory characteristics of PP shape memory fabrics measured by Toray method showed five grade as same value as PTT shape memory fabric. The heat keeping property of the PP shape memory fabric showed 56% higher value than that of PTT shape memory fabric. The water repellency of PP shape memory fabric measured by spray method showed five grade as same value as PTT shape memory fabric treated with water repellent agent. Especially, shape memory properties of PP shape memory fabric measured by 3-D image and camera measurement methods showed similar characteristics to the PTT shape memory fabric.

• Korean Chemical Engineering Research
• /
• v.52 no.5
• /
• pp.553-557
• /
• 2014

Sulfonated polypropylene (S-PP) is prepared by sulfuric acid-acetone aldol condensation reaction of polypropylene (PP) separator to yield hydrophilic separator surface with a moderate amount of $-SO_3H$ groups. Activated carbon supercapacitor is also fabricated adopting the S-PP separator coated with potassium polyacrylate (PAAK) hydrogel polymer electrolyte. As a result, the hydrophilic surface of S-PP separator involves better physical and electrochemical properties such as decrease in contact angle, improvements of wettability, electrolyte uptake, and ionic conductivity to give higher specific capacitance and long cycle-life.