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We investigate the ways of improving thermal and mechanical properties of diglycidyl ether of bisphenol-A (DGEBA) based thermoset resin using diaminodiphenylsulphone (DDS) as hardener and using epoxidized polystyrene/polybutadiene-based triblock copolymers as modifier. The epoxidation was performed. The targeted chemical modification using meta-chloroperoxybenzoic acid (m-CPBA) of the copolymer was performed whereby the epoxidation of the butadiene chains mainly took place at 1,4 linkages. The modification copolymer was found to contribute in enhancing the mechanical performance of the blends with epoxy resin. The results indicated the formation of nanostructured morphology in the blends attributable to their enhanced impact strength. BIBECHANA 16 (2019) 196-203

We investigate the ways of improving thermal and mechanical properties of diglycidyl ether of bisphenol-A (DGEBA) based thermoset resin using diaminodiphenylsulphone (DDS) as hardener and using epoxidized polystyrene/polybutadiene-based triblock copolymers as modifier. The epoxidation was performed. The targeted chemical modification using meta-chloroperoxybenzoic acid (m-CPBA) of the copolymer was performed whereby the epoxidation of the butadiene chains mainly took place at 1,4 linkages. The modification copolymer was found to contribute in enhancing the mechanical performance of the blends with epoxy resin. The results indicated the formation of nanostructured morphology in the blends attributable to their enhanced impact strength. BIBECHANA 16 (2019) 196-203

The butadiene units of polystyrene-block-polybutadiene-block-polystyrene (SBS) triblock copolymer were subjected to epoxidation and subsequent sulphonation in order to prepare proton conducting ionomer membrane. The products were characterized by different techniques such as atomic force microscopy, Fourier transform infrared (FTIR) spectroscopy and electron microscopy. A simple laboratory device was developed to carry out the tests on proton conductance ability of the prepared ionomer membrane. The experiments demonstrated that the prepared membrane excellently performed as proton conducting membrane. DOI: http://dx.doi.org/10.3126/bibechana.v9i0.7174 BIBECHANA 9 (2013) 50-58

The butadiene units of polystyrene-block-polybutadiene-block-polystyrene (SBS) triblock copolymer were subjected to epoxidation and subsequent sulphonation in order to prepare proton conducting ionomer membrane. The products were characterized by different techniques such as atomic force microscopy, Fourier transform infrared (FTIR) spectroscopy and electron microscopy. A simple laboratory device was developed to carry out the tests on proton conductance ability of the prepared ionomer membrane. The experiments demonstrated that the prepared membrane excellently performed as proton conducting membrane. DOI: http://dx.doi.org/10.3126/bibechana.v9i0.7174 BIBECHANA 9 (2013) 50-58

A review of the history of the evolution of material science and material technology shows us that one tendency for the future could be the use of agriculture resources. In this work, we review the performances of one of these resources, that is, wheat flour. We show that it is possible to get thermoplastic films with properties quasiequivalent to what is obtained for expensive pure starch. By adding natural fibres, composites are also obtained. These composites exhibit performances which allow their use only for short duration.

Micro- and nanocrystalline cellulose were extracted from wheat stalk (WS) using different thermomechanical and chemical treatments and characterized by spectroscopic, microscopic and diffraction techniques. The virgin WS fibers were found to be structurally quite similar to the commercial microcrystalline cellulose (MCC). Similar to the commercial one, the MCC extracted from the WS possessed intense infrared (IR) peaks whereas those peaks became more broader in the nanocrystalline cellulose (NCC) of the same origin, which can be attributed to possible breakdown of inter- and intramolecular H-bonding due to strong acid treatment of the MCC. Microscopic results revealed characteristic textures of the MCC and the NCC, the MCC being irregular bundles of the primary crystals bound together with the amorphous phase. The latter was found to disintegrate upon acid hydrolysis giving rise to the rod-shaped nanocrystals having much larger surface area and thus possessing more intense hydrophilic character. The MCC was found to be more stable than the NCC which can be attributed to the presence of protective and binding coating provided by the amorphous cellulosic matter. BIBECHANA 16 (2019) 177-186

Abstract This contribution addresses the relationships between the structure and gas transport properties of nanoporous thermostable cyanate ester resins (CERs) derived from polycyclotrimerization of 1,1′-bis(4-cyanatophenyl)ethane in the presence of 30 or 50 wt% of inert high-boiling temperature porogens (i.e., dimethyl- or dibutyl phthalates), followed by their quantitative removal. The nanopores in the films obtained were generated via a chemically induced phase separation route with further porogen extraction from the densely crosslinked CERs. To ensure a total desorption of the porogen moieties from the networks, an additional short-term thermal annealing at 250 °C was performed. The structure and morphology of such nanoporous CER-based films were investigated by FTIR and SEM techniques, respectively. Further, the gas transport properties of CER films were analyzed after the different processing steps, and relationships between the material structure and the main gas transport parameters were established.

Micro- and nanocrystalline cellulose were extracted from wheat stalk (WS) using different thermomechanical and chemical treatments and characterized by spectroscopic, microscopic and diffraction techniques. The virgin WS fibers were found to be structurally quite similar to the commercial microcrystalline cellulose (MCC). Similar to the commercial one, the MCC extracted from the WS possessed intense infrared (IR) peaks whereas those peaks became more broader in the nanocrystalline cellulose (NCC) of the same origin, which can be attributed to possible breakdown of inter- and intramolecular H-bonding due to strong acid treatment of the MCC. Microscopic results revealed characteristic textures of the MCC and the NCC, the MCC being irregular bundles of the primary crystals bound together with the amorphous phase. The latter was found to disintegrate upon acid hydrolysis giving rise to the rod-shaped nanocrystals having much larger surface area and thus possessing more intense hydrophilic character. The MCC was found to be more stable than the NCC which can be attributed to the presence of protective and binding coating provided by the amorphous cellulosic matter. BIBECHANA 16 (2019) 177-186

In this work, the apparent shear strength at the interface between a bamboo fiber and the surrounding poly(lactic acid) (PLA) matrix is quantified. A method for processing pull-out test samples within a controlled embedded length is proposed and the details of the test procedure are presented, along with a critical discussion of the results. Two series of samples are considered: untreated and mercerized bamboo fibers from the same batch, embedded in the same polyester matrix. Electron and optical microscopy are used to observe the fiber–matrix interface before and after the test, and to identify the failure mode of each sample, especially as regards the occurrence of fibrillation in the fiber bundles. The values of apparent interfacial shear strength are calculated only for regular fibers successfully pulled out from the matrix, and reported with their statistical variations. Mercerization, whose efficiency was proven by Fourier transform infrared (FTIR) spectroscopy, did not appear though to improve the quality of the interface (τapp = 7.0 ± 3.1 MPa for untreated fibers and τapp = 5.3 ± 2.4 MPa for treated fibers).