scholarly journals Corn Starch Reactive Blending with Latex from Natural Rubber in Presence of Na+ Ions of Carboxymethyl Cellulose as a Catalyst

Author(s):  
Noppol Leksawasdi ◽  
Thanongsak Chaiyaso ◽  
Pornchai Rachtanapun ◽  
Pensak Jantrawut ◽  
Warintorn Ruksiriwanich ◽  
...  

Abstract Corn starch (CS) was blended with glycerol, latex natural rubber (LNR), and carboxymethyl cellulose (CMC). The addition of 10 phr of CMC improved the Young’s modulus (6.7 MPa), tensile strength (8 MPa), and elongation at break (80%) of the CSG/LNR blend. The morphology of the CSG/LNR/CMC blends showed a uniform distribution of LNR particles (1–3 µm) in the CSG matrix. The addition of CMC enhanced the swelling ability and water droplet contact angle of the blends owing to the swelling properties, interfacial crosslinking, and amphiphilic structure of CMC. Fourier transform infrared spectroscopy confirmed the reaction between the C=C bond of LNR and the carboxyl groups (–COO-) of CMC, in which Na+ ions in CMC acted as a catalyst. Notably, the mechanical properties of the CSG/LNR/CMC blend were improved owing to the miscibility of CSG/CMC and the CMC/LNR interfacial reaction.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Noppol Leksawasdi ◽  
Thanongsak Chaiyaso ◽  
Pornchai Rachtanapun ◽  
Sarinthip Thanakkasaranee ◽  
Pensak Jantrawut ◽  
...  

AbstractA mixture of corn starch and glycerol plasticizer (CSG) was blended with latex natural rubber (LNR) and carboxymethyl cellulose (CMC). The addition of 10 phr of CMC improved the Young’s modulus (6.7 MPa), tensile strength (8 MPa), and elongation at break (80%) of the CSG/LNR blend. The morphology of the CSG/LNR/CMC blends showed a uniform distribution of LNR particles (1–3 µm) in the CSG matrix. The addition of CMC enhanced the swelling ability and water droplet contact angle of the blends owing to the swelling properties, interfacial crosslinking, and amphiphilic structure of CMC. Fourier transform infrared spectroscopy confirmed the reaction between the C=C bond of LNR and the carboxyl groups (–COO−) of CMC, in which the Na+ ions in CMC acted as a catalyst. Notably, the mechanical properties of the CSG/LNR/CMC blend were improved owing to the miscibility of CSG/CMC and the CMC/LNR interfacial reaction. The CSG/LNR/CMC biodegradable polymer with high mechanical properties and interfacial tension can be used for packaging, agriculture, and medical applications.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Noppol Leksawasdi ◽  
Thanongsak Chaiyaso ◽  
Pornchai Rachtanapun ◽  
Sarinthip Thanakkasaranee ◽  
Pensak Jantrawut ◽  
...  

2018 ◽  
Vol 120 ◽  
pp. 297-301 ◽  
Author(s):  
Kittisak Jantanasakulwong ◽  
Somchai Wongsuriyasak ◽  
Pornchai Rachtanapun ◽  
Phisit Seesuriyachan ◽  
Thanongsak Chaiyaso ◽  
...  

2006 ◽  
Vol 45 ◽  
pp. 1423-1428
Author(s):  
Somsak Woramongconchai ◽  
Chatchawan Lohitvisat ◽  
Aree Wichainchai

The effect of magnetic powders and powders loading on magnetic properties and mechanical properties of magnetic rubbers were studied. The natural rubber with magnetic powders, Barium ferrite, Neodymium iron boron, were used as starting materials to prepare magnetic rubbers. Barium ferrite (BaO.6F2O3) powders had been sintered at 1285 oC for 30 hours to improve its crystal structure. The physical properties of magnetic rubbers, residual flux density (Br), coercive force (Hc), maximum energy product (BHmax), hardness and density, had a trend to increase as enhancing magnetic powders loading. However, some properties such as, intrinsic coercive force (Hci), tensile strength and elongation at break, had a trend to decrease when the magnetic powder loading was increased. Magnetic properties of the anisotropic type, sintered powders, were higher than isotropic type, non-sintered powders, except the Hci because anisotropic magnetic rubber indicated crystal orientation in the same direction.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Thanongsak Chaiyaso ◽  
Pornchai Rachtanapun ◽  
Nanthicha Thajai ◽  
Krittameth Kiattipornpithak ◽  
Pensak Jantrawut ◽  
...  

AbstractCassava starch was blended with glycerol to prepare thermoplastic starch (TPS). Thermoplastic starch was premixed with sericin (TPSS) by solution mixing and then melt-blended with polyethylene grafted maleic anhydride (PEMAH). The effect of sericin on the mechanical properties, morphology, thermal properties, rheology, and reaction mechanism was investigated. The tensile strength and elongation at break of the TPSS10/PEMAH blend were improved to 12.2 MPa and 100.4%, respectively. The TPS/PEMAH morphology presented polyethylene grafted maleic anhydride particles (2 μm) dispersed in the thermoplastic starch matrix, which decreased in size to approximately 200 nm when 5% sericin was used. The melting temperature of polyethylene grafted maleic anhydride (121 °C) decreased to 111 °C because of the small crystal size of the polyethylene grafted maleic anhydride phase. The viscosity of TPS/PEMAH increased with increasing sericin content because of the chain extension. Fourier-transform infrared spectroscopy confirmed the reaction between the amino groups of sericin and the maleic anhydride groups of polyethylene grafted maleic anhydride. This reaction reduced the interfacial tension between thermoplastic starch and polyethylene grafted maleic anhydride, which improved the compatibility, mechanical properties, and morphology of the blend.


2019 ◽  
Vol 52 (8) ◽  
pp. 728-746 ◽  
Author(s):  
Abderrahmane Belhaoues ◽  
Samia Benmesli ◽  
Farid Riahi

The effects of the addition of epoxidized natural rubber/maleic anhydride-grafted polypropylene blend as a compatibilizing agent (CA) on the properties of natural rubber (NR)/polypropylene (PP) thermoplastic elastomer blend were studied. The blends were prepared in the molten state at 180°C using a Brabender Plasticorder at a rotor speed of 60 r min−1. Evidence of compatibilization was obtained from the Brabender plastograms and from the mechanical properties results as well as the morphological analysis. It was found that the addition of the CA at different contents resulted in an increase of the tensile strength and Young’s modulus and a decrease of the elongation at break. It was also found that the melting temperature remained unchanged, the % crystallinity decreased, but the thermal stability was not affected. The morphology revealed a more homogeneous distribution of the dispersed PP phase for the CA-containing systems compared to the control NR/PP blend. These effects were attributed to the interactions that developed with the blend constituents through the functional groups of the CA.


2005 ◽  
Vol 21 (3) ◽  
pp. 183-199
Author(s):  
G.K. Jana ◽  
C.K. Das

De-vulcanization of vulcanized elastomers represents a great challenge because of their three-dimensional network structure. Sulfur-cured gum natural rubbers containing three different sulfur/accelerator ratios were de-vulcanized by thio-acids. The process was carried out at 90 °C for 10 minutes in an open two-roll cracker-cum-mixing mill. Two concentrations of de-vulcanizing agent were tried in order to study the cleavage of the sulfidic bonds. The mechanical properties of the re-vulcanized rubber (like tensile strength, modulus, tear strength and elongation at break) were improved with increasing concentrations of de-vulcanizing agent, because the crosslink density increased. A decrease in scorch time and in optimum cure time and an increase in the state of cure were observed when vulcanized rubber was treated with high amounts of de-vulcanizing agent. The temperature of onset of degradation was also increased with increasing concentration of thio-acid. DMA analysis revealed that the storage modulus increased on re-vulcanization. From IR spectroscopy it was observed that oxidation of the main polymeric chains did not occur at the time of high temperature milling. Over 80% retention of the original mechanical properties (like tensile strength, modulus, tear strength and elongation at break) of the vulcanized natural rubber was achieved by this mechanochemical process.


2017 ◽  
Vol 735 ◽  
pp. 153-157
Author(s):  
Wasinee Pinpat ◽  
Wirunya Keawwattana ◽  
Siree Tangbunsuk

Silica has been used as reinforcing filler in natural rubber for a period of time as it results in excellent properties for NR vulcanizes. Rice husk ash (RHA), bagasse ash (BA), and oil palm ash (OPA) obtained from agricultural wastes are mainly composed of silica in the percentage of 80.00%, 57.33%, and 40.20% by weight, respectively. The effect of these fillers on cure characteristics and mechanical properties of natural rubber materials at fixed silica content at 35 parts per hundred of rubber (phr) were investigated. The results indicated that ashes showed greater cure time compared to that of the silica. The incorporation of ashes into natural rubber gradually improved compression set but significantly decreased tensile strength, elongation at break, and resilience. Moreover, young's modulus increased, while hardness showed no significant change with the addition of ashes. Overall results indicated that ashes could be used as cheaper fillers for natural rubber materials where improved mechanical properties were not critical.


2013 ◽  
Vol 772 ◽  
pp. 34-37
Author(s):  
Hao Tang ◽  
Hai Tian Jiang ◽  
Bin Guo ◽  
Pan Xin Li

Corn starch was irradiated by 60Coγ ray, and then the thermoplastic starch plastic (TPS) was prepared by adding glycerol. Microstructure, thermal and mechanical properties of the corn starch and starch plastic were studied in details by FTIR, DSC and SEM. Results showed that the starch macromolecular structure was damaged by irradiation, and with increased irradiation time, the temperature of melt endothermic peak and tensile strength decreased, elongation at break increases for starch plastic, the thermoplastic property of starch was enhanced obviously.


2013 ◽  
Vol 773 ◽  
pp. 668-672
Author(s):  
Jun Liang Liu ◽  
Ping Liu ◽  
Xiao Qiang Tang ◽  
Dong Zeng ◽  
Xing Kai Zhang ◽  
...  

In this paper, the blends of natural rubber with waste ground rubber powders have been prepared by mechano-chemical activation method. The influences of particle sizes on both processing performances and mechanical properties have been investigated. The results indicated that: the blends with waste ground rubber powders of smaller particle sizes approached to higher surface tensile and easily mechano-chemical activation, which led to the formation of complete homogenous re-vulcanization cross-linking structure and resulted in the improvements of the whole performances of the final products. The tensile strength, the elongation at break and tear strength approached to the highest value of 20.7MPa, 530% and 33.0 kN/m as the 100mesh waste ground rubber powders were used as the starting materials.


Sign in / Sign up

Export Citation Format

Share Document