Characterization of the Aniline.DBSA/Thermoplastic Polyurethane Blends for the Thermo-Mechanical and Electro-Mechanical Properties

Conducting polymer blends Polyaniline-Dodecylbenzene sulfonic acid (Pani.DBSA) and thermoplastic polyurethane (TPU) were prepared using in-situ emulsion polymerization method by dissolving both components in DMF. Ani.DBSA/TPU blends were prepared with different compositions 20/80, 30/70, 40/60 and 50/50 wt%. Theses blends have good conducting and mechanical properties. Blends were characterized by Potentiostate, Thermogravimetric analysis (TGA), Infrared spectroscopy (FTIR) and Dynamic mechanical thermal analyzer (DMTA). The electrical conductivity increases up to 30 wt% loading of aniline.DBSA after that it decreases gradually. The uniform dispersion of aniline.DBSA showed in SEM images which is the indication of a strong connection between aniline.DBSA and TPU which increase the conductivity. These blends can be used as strain sensors.

Enhancing the Mechanical and Thermal Properties of Epoxy Resin via Blending with Thermoplastic Polysulfone

Efficient enhancement of the toughness of epoxy resins has been a bottleneck for expanding their suitability for advanced applications. Here, polysulfone (PSF) was adopted to toughen and modify the epoxy. The influences of PSF on the mechanical and thermal properties of the epoxy resin were systematically studied by optical microscopy, Fourier transform infrared spectrometer (FT-IR), differential scanning calorimetry (DSC), thermogravimetric analyzer (TG), dynamic mechanical thermal analyzer (DMA), mechanical tests and scanning electron microscope (SEM). The dissolution experimental results showed that PSF presents a good compatibility with the epoxy resin and could be well dissolved under controlled conditions. The introduction of PSF was found to promote the curing reaction of the epoxy resin without participating in the curing reaction and changing the curing mechanism as revealed by the FT-IR and DSC studies. The mechanical properties of PSF/epoxy resin blends showed that the fracture toughness and impact strength were significantly improved, which could be attributed to the bicontinuous phase structure of PSF/epoxy blends. Representative phase structures resulted from the reaction induced phase separation process were clearly observed in the PSF/epoxy blends during the curing process of epoxy resin, which presented dispersed particles, bicontinuous and phase inverted structures with the increase of the PSF content. Our work further confirmed that the thermal stability of the PSF/epoxy blends was slightly increased compared to that of the pure epoxy resin, mainly due to the good heat resistance of the PSF component.

STUDIES OF MONOMER IMPREGNATION AND POLYMERIZED “IN-SITU” IN WOOD USING DYNAMIC MECHANICAL THERMAL ANALYZER (DMTA)

Some tropical hardwoods (acacia mangium, madhuca utilis, dacrydium spp., dipterocarpus spp.,dyera costulata, shorea spp., shorea gibbosa, shorea macrophylla, endospermum diadenum, cratoxylum arborescens) are selected and impregnated with methyl methacrylate (MMA) and polymerized “in-situ” by using catalyst-heat technique. Treatability of the wood as determinedfrom the fractional volumetric retentions of monomer i.e. fraction of voids filled by the impregnant showed that the mean retention range from 15.03% (acacia mangium) to 56.59% (cratoxylum arborescens). The penetration of monomer evaluated using ultrasonic wave showed that the treated wood had higher velocities which indicate significant increase in density. This paper deals with the viscoelastic relaxation of polymerized treated wood. The efficiency of monomer as a plasticizer is studied through the temperature dependence of the storage modulus (E´) and loss tangent (tan d) of treated and untreated wood by dynamic mechanical thermal analysis (DMTA) over a temperature of -100 to 200ºC. E´ decrease with temperature, and as the maximum mechanical damping develop, the glass transition temperature (Tg) of plasticized wood decrease with the plasticizer content.

Properties of MWCNT–glass fiber fabric multiscale composites: mechanical properties, interlaminar adhesion, and thermal conductivity

In this study, multiscale MWCNT–glass fiber fabric (MGFf) preforms with multiwalled carbon nanotubes (MWCNTs) dispersed onto commercial E-glass fiber fabric (GFf) was used to fabricate the MGFf multiscale composites. The mechanical properties, interlaminar shear strength (ILSS), dynamic viscoelasticity and thermal conductivity of MGFf multiscale composites were investigated using a universal material testing machine, dynamic mechanical thermal analyzer and transient plane source method. Furthermore, the reinforcing mechanisms of MWCNTs on interlaminar adhesion of MGFf multiscale composites were explored using scanning electron and transmission electron microscopy and energy dispersive X-ray spectrometry. Compared with the GFf composite, the ILSS and thermal conductivity of MGFf multiscale composites were increased by 40.5% and 55.3%, respectively; both of the tensile and flexural properties of MGFf multiscale composites were significantly enhanced; the glass transition temperature of MGFf multiscale composites was also raised. In addition, the interface thickness was increased with the addition of MWCNTs, and MWCNTs in MGFf multiscale composites behaved as hooked fibers to improve the interlaminar adhesion. The work demonstrates the great promise of MGFf preforms toward practical industrial application in manufacturing multifunctional fiber composites with high strength and modulus, high shear resistance and good thermal conductivity.

Valorization of industrial by-products through bioplastic production: defatted rice bran and kraft lignin utilization

The objective of this study was to develop a bioplastic from industrial by-products. Commercial defatted rice bran (DRB) was extruded with 0–30% kraft lignin (KL) as a filler and 30% glycerol as a plasticizer. Firstly, the effect of extrusion temperature on the plasticized DRB’s processability was determined. Increasing the die extrusion temperature from 100°C to 150°C improved the extrudability by decreasing the die pressure and motor current. Subsequently, the effect of KL on plasticized DRB was studied. The addition of 10–30% KL improved DRB processability. The addition of 30% KL markedly lowered the die pressure in comparison to using a 150°C extrusion temperature. Moreover, KL addition decreased DRB viscosity determined by a capillary rheometer. These results were coherent with a decreased storage modulus in a rubber state and an increased tan δ height determined by a dynamic mechanical thermal analyzer (DMA). However, n values of DRB with 10–30% KL could not be explained by a simple mixing rule. This may be attributed to the interaction between DRB and KL, as shown by Fourier transform infrared (FTIR) spectra. KL addition increased Young’s modulus and the glass transition temperature (Tg) of plasticized DRB. Therefore, blending DRB with KL is an effective way to improve polymer flowability at the processing temperature and mechanical properties at ambient temperature.

Experimental Investigation of Dynamic Viscoelasticity of Bamboo with Different Ages

The dynamic viscoelasticity of the outer and inner part of bamboo with different ages was investigated using Dynamic Mechanical Thermal Analyzer (DMA). The results showed that,storage modulus (E’) and loss modulus (E’’) of both outer and inner part of bamboo were increased at temperature between 25-250°Cas the bamboo ages increasing. In addition, E’ and E’’ of the outer part of bamboo were higher of the inner part with the same bamboo age. Also a significant loss peak in E’’~T curves between 190-210°C was found. The peak values of E’’~ T curves of the outer part only shown slight variation with bamboo age increasing. However, significantly different of peak values was found in the inner part. This was caused by the difference of the chemical composition in outer and inner part of bamboo with different ages. The width of E’’ peak varied slightly in outer bamboo of different ages, but in the inner part , it was increased as the age increasing. This revealed that in the outer part of different ages, the chemical composition of the molecular values was closer, In the inner bamboo, it was increased as the age increasing..

SIFAT DINAMIK MEKANIKAL VULKANISAT KARET ALAM-ORGANOCLAY

Sifat dinamik dan swelling vulkanisat karet alam (NR) yang mengandung bahan pengisi organoclay dengan basal spasi yang berbeda telah dipelajari. Vulkanisat NR/organoclay dibuat dengan menggunakan metode pelelehan kompon di dalam gilingan terbuka. Sifat dinamik diukur dengan menggunakan Dynamic Mechanical Thermal Analyzer (DMTA). Hasil penelitian menunjukkan bahwa penambahan organoclay dengan basal spasi lebih besar (15A) menghasilkan struktur interkalasi/eksfoliasi di dalam matrik karet alam sehingga sifat dinamik mekanikal dan swelling menjadi lebih baik. Storage modulus di bawah Tg dan di atas Tg meningkat dengan peningkatan basal spasi organoclay. Adanya organoclay juga menyebabkan penurunan tan d dan Tg vulkanisat, terutama organoclay 15A. Organoclay 15A di dalam vulkanisat karet alam dapat menurunkan nilai swelling dan koefisien difusi, sorptivitas serta permeabilitas. Derajat ikatan silang dari NR/organoclay 15A sedikit lebih besar dan memperbaiki sifat elastis vulkanisat. Diterima : 7 Januari 2013; Disetujui : 24 April 2013How to Cite : Faturrohman, M., Soegijono, B., Budianto, E., & Yoneda, K. (2013). Sifat Dinamik Mekanikal Vulkanisat Karet Alam-Organoclay. Jurnal Penelitian Karet, 31(1), 45-53. Retrieved from http://ejournal.puslitkaret.co.id/index.php/jpk/article/view/132

SIFAT DINAMIK MEKANIKAL VULKANISAT KARET ALAM-ORGANOCLAY

Sifat dinamik dan swelling vulkanisat karet alam (NR) yang mengandung bahan pengisi organoclay dengan basal spasi yang berbeda telah dipelajari. Vulkanisat NR/organoclay dibuat dengan menggunakan metode pelelehan kompon di dalam gilingan terbuka. Sifat dinamik diukur dengan menggunakan Dynamic Mechanical Thermal Analyzer (DMTA). Hasil penelitian menunjukkan bahwa penambahan organoclay dengan basal spasi lebih besar (15A) menghasilkan struktur interkalasi/eksfoliasi di dalam matrik karet alam sehingga sifat dinamik mekanikal dan swelling menjadi lebih baik. Storage modulus di bawah Tg dan di atas Tg meningkat dengan peningkatan basal spasi organoclay. Adanya organoclay juga menyebabkan penurunan tan d dan Tg vulkanisat, terutama organoclay 15A. Organoclay 15A di dalam vulkanisat karet alam dapat menurunkan nilai swelling dan koefisien difusi, sorptivitas serta permeabilitas. Derajat ikatan silang dari NR/organoclay 15A sedikit lebih besar dan memperbaiki sifat elastis vulkanisat. Diterima : 7 Januari 2013; Disetujui : 24 April 2013How to Cite : Faturrohman, M., Soegijono, B., Budianto, E., & Yoneda, K. (2013). Sifat Dinamik Mekanikal Vulkanisat Karet Alam-Organoclay. Jurnal Penelitian Karet, 31(1), 45-53. Retrieved from http://ejournal.puslitkaret.co.id/index.php/jpk/article/view/132

Role of Epoxidized Natural Rubber in Dynamic Mechanical Properties of NR/ENR/silica Composites

NR/ENR/silica composites with different ENR amount were prepared in an open two-roll laboratory mixing mill at room temperature. Dynamic properties of ENR filled NR/silica were performed by dynamic mechanical thermal analyzer (DMA) and compression fatigue analyzer. DMA and compression fatigue test results showed that the effect of ENR on dynamic properties of NR/silica was significant. DMA displayed the tanδ of NR/ENR/silica composites at 0 °C was increased with increasing ENR amount. Compression fatigue test indicated the presence of ENR decreased the heat produced during compression test and the heat build-up is the least when NR to ENR ratio is 80 to 20. Scanning electron microscopy was used to investigate the morphology of NR/silica filled with ENR. It is found that silica self-aggregation was improved in the presence of ENR and sea-island structure was formed in NR/silica when 30phr ENR added, which maybe the reason of decrement of heat produced during compression.

Damping Behavior and Mechanism of Graphite and Al2O3 Particles Reinforced Al Matrix Composites

The graphite and alumina particles reinforced Al matrix composites with graphite up to 5 vol% was prepared by Reciprocating Extrusion (RE). Damping behavior of the composites was measured by dynamic mechanical thermal analyzer. The composites showed more excellent damping Q-1 than pure Al manufactured by RE, and the ambient value was 9.9×10-3 at 5 Hz when the strain amplitude was 8×10-8. The damping behavior of the composites showed slight variation with frequency. The damping capacity increased with increasing of the strain amplitude when the amplitude less than 1.5×10-6, and then became a constant and independent of strain amplitude. The high damping capacity was attributed to micro-sliding interface damping and the dislocation damping.