Improving Mechanical Properties of Poly-β-Hydroxybutyrate-co-β-Hydroxyvalerate by Blending with Natural Rubber and Epoxidized Natural Rubber

2014 ◽  
Vol 983 ◽  
pp. 179-182 ◽  
Author(s):  
Maneewong Chutamas ◽  
Sunthornvarabhas Jackapon ◽  
Joong Kim Hyun ◽  
Sriroth Klanarong

Poly-β-hydroxybutyrate-co-β-hydroxyvalerate (PHBV) is a bacterial-synthesized biopolymer. Moreover, PHBV is a biodegradable, it is an interesting biopolymer for disposable products. PHBV is difficult to process due to its low toughness, an elastic polymer such as natural rubber is introduced to develop toughness. In this experiment, PHBV mechanical properties were improved by blending with natural rubber (NR) and epoxidized natural rubber (ENR). The NR/PHBV and ENR/PHBV blends with the same ratio of 10/90 (wt/wt) could be extruded, whereas other conditions could not. This ratio was then used throughout this study to examine effect of maleic anhydride (MA) and benzoyl peroxide (BPO) to improve toughness of the blends. Result showed at composition where 1.0 % (wt/wt) MA and 0.05 % (wt/wt) BPO was mixed (coding EPMB2), several aspects of mechanical properties were improved. The blend, EPMB2 revealed the highest impact strength, significantly improved of elongation but drastically decreased of tensile strength. Storage modulus slightly decreased, tangent delta significantly increased when compared with neat PHBV.

2018 ◽  
Vol 14 (3) ◽  
pp. 348-352 ◽  
Author(s):  
Nur Amira Sahirah Abdullah ◽  
Zurina Mohamad

Poly (lactic acid)/epoxidized natural rubber (PLA/ENR) was prepared by using counter-rotating twin-screw extruder. For dynamic vulcanization process, ENR was compounded with 3 phr of N, N’-m-phenylenebismaleimide (HVA-2) as a crosslinking agent. The aim of this study is to determine the effect of unvulcanized and dynamically vulcanized of ENR on the properties of PLA/ENR blend. The blending of PLA with ENR was prepared with the various composition of ENR (0 wt% to 30 wt%). The morphology and mechanical properties of the blends were investigated by using scanning electron microscope (SEM), tensile test, and impact test. The unvulcanized blend produced a co-continuous morphology of PLA and ENR and the dynamically vulcanized blend shows the dispersed ENR rubber particles in PLA continuous matrix.  For both systems, the tensile strength value was dropped with the increasing amount of ENR content. The impact strength of both systems shows the maximum value at 20 wt% of ENR content. However, dynamically vulcanized PLA/ENR blend shows a better tensile strength and impact strength value as compared with unvulcanized blend.


2020 ◽  
Vol 990 ◽  
pp. 262-266
Author(s):  
Prathumrat Nu-Yang ◽  
Atiwat Wiriya-Amornchai ◽  
Jaehoon Yoon ◽  
Chainat Saechau ◽  
Poom Rattanamusik

Thermoplastic vulcanizates or TPVs is a type of materials exhibiting excellent properties between thermoplastic and elastomer by combining the characteristics of vulcanized rubber with the processing properties of thermoplastics. This research aims to study the effect of thermal aging on the morphology and mechanical properties of thermoplastic vulcanizates (TPVs) based on a mixture of natural rubber (NR) and polystyrene (PS). TPVs samples were prepared using the internal mixer at a mass ratio of NR/PS 70/30, 50/50, 30/70 and 0/100. Tensile properties and impact strength showed that when the amount of NR increased tends of impact strength and elongation at break increased but tends of tensile strength decreased. On the other hand, tends of tensile strength for thermal aging at 70°C for 3 days increased when the amount of PS increase. The blending ratio of NR / PS at 70/30 is the best. It gave a worthy increase from 19.94 MPa to be 25.56 MPa (28.18%).


2012 ◽  
Vol 602-604 ◽  
pp. 690-695
Author(s):  
Hua Dong Wang ◽  
Rui Wang ◽  
Mao Fang Huang ◽  
Qi Yang

Thermoplastic vulcanizates (TPVs) based on epoxidized natural rubber (ENR) and polypropylene (PP) were prepared in an internal mixer at 180°C. The effects of curing systems (i.e., sulfur and peroxide) on morphological, rheological, thermal and mechanical properties were studied. It is found that the sulfur cured TPVs show higher tensile strength, tear strength and elongation at break than those cured with the DCP systems. The rheological analysis indicates that TPVs cured with DCP system show lower apparent shear viscosity than those with sulfur system. SEM studies show that TPVs vulcanized with DCP system exhibit smaller and finely dispersed rubber domains, which provides it higher thermal stability than sulfur cured TPVs.


2013 ◽  
Vol 747 ◽  
pp. 375-378 ◽  
Author(s):  
Chaiwat Ruksakulpiwat ◽  
Wasaphon Wanasut ◽  
Apikiat Singkum ◽  
Ruksakulpiwat Yupaporn

This research shows a great potential of cogon grass fiber to be used as a reinforcement in epoxidized natural rubber composites. The thermal and mechanical properties of cogon grass fiber-epoxidized natural rubber composites were studied. The chemical treatment of cogon grass fiber to be used as a reinforcing filler was revealed. Effects of fiber treatment method and treatment time of cogon grass fiber on thermal properties of the fibers and their composites were elucidated. The addition of cogon grass fiber into epoxidized natural rubber (ENR) improved the mechanical properties of the composites.The result indicated that alkaline treatment followed by acid treatment of cogon grass fiber led to an increase in thermal decomposition temperature and mechanical properties of the composites more than that without acid treatment. With increasing the amount of fiber, tensile strength of ENR composites were significantly increased while elongation at break was insignificantly changed. ENR with the addition of 4-Amino-6-hydroxy-2-mercaptopyrimidine monohydrate as coupling agent (ENRC) was shown to have higher tensile strength, modulus at 200% elongation and elongation at break than ENR. Improved mechanical properties were also obtained in ENRC composites compared to those of ENR composites.


2014 ◽  
Vol 695 ◽  
pp. 273-276 ◽  
Author(s):  
Nor Nisa Balqis Mohammad ◽  
Agus Arsad ◽  
Abdul Razak Rahmat ◽  
S.Z. Mat Des ◽  
Nur Syazana Abdullah Sani

Polylactic acid (PLA)/ Natural rubber (NR) in the presence of PLA grafted Maleic Anhydride (PLAGMA) as compatibilizer was prepared by the melting blend method. In attempt to achieve high performance of the blend, nanocomposites were formed by incorporating different ratio of carbon nanotube (CNT) in PLA/NR/PLAGMA blend. The effect of CNT content on mechanical properties was investigated. With increasing CNT content, Young’s modulus and flexural modulus were increased firstly and then decreased as CNT was further added. In other hand, impact strength was dropped as expected as the CNT loading was increased.


2016 ◽  
Vol 30 (3) ◽  
pp. 341-357 ◽  
Author(s):  
Qin Tian ◽  
Shuhao Qin ◽  
Fuzhong Wu ◽  
Huixin Jin ◽  
Ming Yang ◽  
...  

Polypropylene (PP)/ethylene acrylic acid (EAA)/maleic anhybride-grafted PP (PP- g-MA)/organoclay nanocomposites were prepared using the melt mixing technique, and PP- g-MA and EAA were employed as the compatibilizers. The sodium montmorillonite (MMT) were pretreated with high-speed airflow pulverization method and then grafted using γ-glycidoxypropyltrimethoxysilane, followed by modification using trihexyltetradecylphosphonium chloride cation with supercritical carbon dioxide as the reaction medium (the obtained product was abbreviated as OGMMT). The modification of MMT was characterized by thermogravimetric analysis, X-ray diffraction (XRD), and scanning electron microscopy. The effect of organoclay content on microstructure and mechanical properties of PP/EAA/PP- g-MA/OGMMT nanocomposites was investigated by XRD, transmission electron microscopy, dynamic mechanical analysis, tensile strength, notched impact strength, flexural strength, and flexural modulus. The results show that the OGMMT has a high weight loss, a large d-spacing increment, and exfoliation predomination structure. The addition of compatibilizers benefited the formation of exfoliated structure and the dispersion of OGMMT in PP matrix, and hence, enhanced the storage modulus ( G′) below the glass transition temperature ( Tg), storage modulus ( G″), Tg, tensile strength, flexural strength, and flexural modulus of the nanocomposites. Furthermore, with the increasing OGMMT content, the nanocomposites exhibited very inconsiderable alteration in the clay dispersion level and enhanced G′ below the Tg, G″, tensile strength, flexural strength, and flexural modulus of the nanocomposites, whereas the Tg was invariant. As a whole, the introduction of compatibilizers and OGMMT led to the reduction of notched impact strength, which also nearly linearly decreased with increasing clay content.


2012 ◽  
Vol 488-489 ◽  
pp. 62-66
Author(s):  
Jareenuch Rojsatean ◽  
Supakij Suttireungwong ◽  
Manus Seadan

The blend of poly(styrene-co-acrylonitrile) (SAN) and natural rubber (NR) is immiscible and incompatible which lead to poor mechanical properties. Many methods can be carried out to improve the compatibility. In this work, the potential of various reactive compatibilizers in SAN and NR blend was explored. The morphological and mechanical properties were compared. The melt blending of SAN and NR were prepared in an internal mixer with various types of reactive agent such as styrene-co-maleic anhydride (SMA), maleic anhydride (MA), peroxide and mixed reactive agents. The morphological textures of the blends were investigated by scanning electron microscope. Mechanical properties including tensile strength, impact strength and elongation at break were measured. The results of morphological observations revealed that SAN/NR blend with reactive agent, the mixture of SMA and MA show the smallest and the most uniform dispersed NR particles, where the size of NR particle is about 1 µm. The mechanical properties of the blends revealed impact strength and elongation at break were increased with addition of reactive agents. SAN/NR blend with the mixture of SMA and MA showed the highest elongation at break but it had lower impact strength than the blend with SMA.


2012 ◽  
Vol 576 ◽  
pp. 394-397 ◽  
Author(s):  
Noor Azlina Hassan ◽  
Hassan Norita ◽  
Sahrim Haji Ahmad ◽  
Rozaidi Rasid ◽  
Hazleen Anuar ◽  
...  

Thermoplastic natural rubber (TPNR) nanocomposites were prepared by melt blending method with the optimum mixing parameters (140oC, 100 rpm, 12 min) using internal mixer (Haake 600 P). The aim of this work is to study the effects of organo-montmorillonite (OMMT) on the physical and mechanical properties of TPNR with and without coupling agent (maleic anhydride grafted polyethylene, MA-PE). Significant improvement in tensile strength and modulus of TPNR nanocomposites were obtained with the presence of MA-PE.


2015 ◽  
Vol 659 ◽  
pp. 463-467
Author(s):  
Sirirat Wacharawichanant ◽  
Parida Amorncharoen ◽  
Ratiwan Wannasirichoke

The effects of polypropylene-graft-maleic anhydride (PP-g-MA) compatibilizers on the morphology and mechanical properties of polyoxymethylene (POM)/acrylonitrile-butadiene-styrene (ABS) blends were investigated. Two types of compatibilizers, PP-g-MA with maleic anhydride 0.50 wt% (PP-g-MA1) and PP-g-MA with maleic anhydride 1.31 wt% (PP-g-MA2) were used to study the interfacial adhesion of POM and ABS. POM/ABS blends with and without PP-g-MA compatibilizer were prepared by an internal mixer and molded by compression molding. Scanning electron microscope (SEM) was used to investigate the morphology of ABS phase in POM matrix. The results found that POM/ABS blends clearly demonstrated a two phase separation of dispersed ABS phase and the POM matrix phase, and ABS phase dispersed as spherical domains in POM matrix in a range of ABS 10-30 wt% and the blends containing ABS more than 30 wt% showed the elongated structure of ABS phase. The addition of PP-g-MA could improve the interfacial adhesion of POM/ABS blends due to the domain size of ABS phase decreased after adding PP-g-MA. The mechanical properties showed that the impact strength of POM/ABS blends decreased in a range of 10-20 wt% and did not change after 20 wt%. The addition of PP-g-MA did not change the impact strength of POM/ABS blends. The Young’s modulus of POM/ABS blends increased up to 30 wt% of ABS and then decreased. While the blends showed the decrease of tensile strength and percent strain at break with increasing ABS content. The addition of PP-g-MA increased the tensile strength of POM/ABS blends in a range of 30-40 wt% of ABS. The above results indicated that the morphology had an effect on the mechanical properties of polymer blends.


1941 ◽  
Vol 14 (4) ◽  
pp. 899-913 ◽  
Author(s):  
E. Gartner

Abstract On the basis of the investigations described in the present paper, certain rules or directions for obtaining the most desirable properties with the various types of artificial rubbers can be laid down. Brinell hardness.—The higher the proportion of vinyl component in a mixed butadiene polymer, the harder is the resulting vulcanizate within the relatively narrow range of percentages of sulfur which were tested. In this respect, acrylonitrile has a greater effect than does styrene. Mechanical properties.—As far as mechanical properties are concerned, Perbunan-Extra is an extraordinarily good material for, in addition to giving high Brinell hardness and tensile strength, it also shows good shock resistance and impact strength. Buna-SS and Perbunan-Extra give, within the range of hardnesses tested, high Martens values. Compared with natural rubber, their resistances to dynamic bending are particularly good.


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