• Elastomers and Composites
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• v.51 no.3
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• pp.175-180
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• 2016

Influence of amino acidic chemical on properties of maleic anhydride-grafted ethylene-propylene-diene terpolymer/zinc oxide (EPDM-g-MAH/ZnO) composites was investigated. 4-Aminosalicylic acid (ASA), 4-amino-2-methoxybenzoic acid (AMBA), 12-aminolauric acid (ALA), and glutamine (Gln) were employed as the amino acidic chemicals. Though small quantity (0.5 phr) of the amino acidic chemical was added to the EPDM-g-MAH/ZnO composite, the properties were notably changed. By adding the amino acidic chemical, the percent crystallinity and apparent crosslink density were reduced. Order of the percent crystallinity was related to that of the $pK_a$ values of amino acidic chemicals. By adding the amino acidic chemical, the basic tensile properties were on the whole improved. The experimental results were explained by the $pK_a$ values of amino acidic chemicals, change of zinc ionomer formation, and interactions between the additive and EPDM-g-MAH chain.

• Elastomers and Composites
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• v.35 no.1
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• pp.46-52
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• 2000

Miscibility improvement between polypropylene(PP) and ethylene-propylene-diene-terpolymer (EPDM) was studied by introducing specific interaction into both polymers. PP was modified by grafting maleic anhydride(MAH) onto backbone, leading to MAH-grafted PP(PP-g-MAH). Sulfonated EPDM ionomer neutralized with bivalent zinc cation(ZnSEPDM) was used as one component. The blends of PP-g-MAH and ZnSEPDM were prepared at $200^{\circ}C$ in Brabender Roller Mixer. Fourier transform-infrared(FT-IR) spectroscopic and dynamic mechanical studies have been performed to investigate the miscibility. FT-IR spectral peak corresponding to carbonyl group in PP-g-MAH and that to sulfonate group in ZnSEPDM were shifted to lower and higher frequency with increasing ZnSEPDM content, respectively, in the blends. Glass transition temperature of ZnSEPDM was increased up to 70wt.% of ZnSEPDM, and again decreased above 70wt.%. It can be concluded from the shift of FT-IR characteristic peaks and the changes of glass transition temperatures that the miscibility between PP and EPDM was improved via introducing specific interaction, i.e., dipole-ion interaction.

• Elastomers and Composites
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• v.48 no.4
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• pp.288-293
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• 2013

Crosslink characteristics of maleic anhydride-grafted EPDM (MAH-g-EPDM)/zinc oxide composite were investigated by weight losses after dichloroacetic acid (DCA)/toluene cosolvent extraction at different temperatures and by measurement of crosslink densities. The chemical changes were analyzed using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The weight losses by extraction at high temperature ($90^{\circ}C$) were remarkably greater than those at room temperature and those by DCA/toluene cosolvent extraction were greater than those by toluene one by more than 5 times. The crosslink densities were measured after the solvent extraction, and the second crosslink densities were higher than the first ones. The first crosslink density was lower when the extraction temperature was high, and it was much lower for the toluene extraction than for the DCA/toluene cosolvent extraction. The second crosslink density of the sample extracted with DCA/toluene cosolvent was greater than that extracted with toluene. The extracted components were depending on the extraction solvents and temperatures, for example; only strong crosslinked networks were remained when extracting with DCA/toluene cosolvent at high temperature, while only uncrosslinked polymer chains were extracted when extracting with toluene at room temperature. Therefore, crosslink characteristics of the MAH-g-EPDM/zinc oxide composite can be analyzed by comparison of the extracted components according to the extraction solvents and temperatures and by measurement of successive crosslink densities.

• Korean Chemical Engineering Research
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• v.49 no.3
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• pp.342-347
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• 2011

The effects of compatibilizers on the mechanical and rheological properties of PP/PCL and TPO/PCL blends have been studied. The thermoplastic polyolefin (TPO) consists of PP (80 wt%), EPDM (15 wt%) and Talc (5 wt%). Maleic anhydride grafted polypropylene (PP-g-MAH) and maleic anhydride grafted styrene-(ethylene-co-butene)-styrene copolymer (SEBS-g-MAH) were used as compatibilizers. In mechanical properties of PP/PCL and TPO/PCL blends, tensile strength was increased when PP-g-MAH was used as a compatibilizer, and impact strength was increased when SEBS-g-MAH was used as a compatibilizer. From the results of SEM morphology of PP/PCL blend, PCL droplet size was decreased by the addition of PP-g-MAH. From the results of rheological property, complex viscosity of the PP/PCL and TPO/PCL blends did not change appreciably when the compatibilizers were added. From the results of mechanical, morphological and rheological properties of the blends, PP-g-MAH acted as a compatibilizer to increase the tensile strength of the PP/PCL and TPO/PCL blends. While SEBS-g-MAH acted as a impact modifier to increase the impact strength of the PP/PCL and TPO/PCL blends.

• Elastomers and Composites
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• v.48 no.1
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• pp.55-60
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• 2013

Swelling behaviors of raw (Specimen-R) and compressed (Specimen-C) samples of maleic anhydride-grafted EPDM (MAH-g-EPDM) depending on the treatment with dichloroacetic acid were investigated. Structural characteristics of the samples were analyzed by nuclear magnetic resonance spectroscopy (NMR) and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). When the samples were not treated with dichloroacetic acid, the swelling ratio of Specimen-R was greater than that of Specimen-C by about twice and the swelling ratio change was negligible though the process of swelling and drying was repeated. When the samples were treated with dichloroacetic acid, the first swelling ratios were increased but the second ones were decreased. For the Specimen-C, the swelling ratio of the sample without the dichloroacetic acid treatment and the second swelling ratio of the sample treated with dichloroacetic acid were nearly the same. However, for the Specimen-R, the second swelling ratio of the sample treated with dichloroacetic acid was strikingly lower than that of the sample without the dichloroacetic acid treatment. The swelling ratio change according to the dichloroacetic acid treatment was explained by dissociation of the existing crosslinks and formation of new crosslinks.

• Polymer(Korea)
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• v.36 no.5
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• pp.549-554
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• 2012

It was known that triphenyl phosphate wasn't homogeneously dispersed in HDPE/EPDM/boron carbide blends, which caused the decrease in mechanical properties. HDPE, EPDM, boron carbide, and triphenyl phosphate were blended with PE-g-MAH(polyethylene-graft-maleic anhydride) as a compatiblizer for improving the miscibility of triphenyl phosphate. Tensile strength of HDPE/EPDM/boron carbide blends decreased with increasing the contents of triphenyl phosphate for flammability. However, the mechanical properties of HDPE/EPDM/boron carbide/triphenyl phosphate blends increased by the addition of compatiblizer because triphenyl phosphate was homogeneously mixed in the blend system. The homogeneous dispersibility of triphenyl phosphate was confirmed by using scanning electron microscopy (SEM). Increased thermal stability and flammability derived from high miscibility of triphenyl phosphate were confirmed by the results of thermogravimetric analysis (TGA) and limiting oxygen index (LOI). A self-extinguishing HDPE/EPDM/boron carbide/triphenyl phosphate blend was successfully fabricated with more than 21% LOI.