Two fungi, responsible for the degradation of starch/polyvinyl alcohol (PVA) biocomposite films were isolated from aerobic compost environment by extensive screening. ITS (Internal Transcribed Spacer) sequencing of the two fungi samples showed 99% identity at 99% coverage with the sequence from Penicillium daleae, and 100% identity at 100% coverage with the sequence from Aspergillus flavus. An extensive weight loss study was performed using these two fungi on starch/PVA films separately. In comparison to the weight loss observed in the compost (nearly 60%), starch/PVA films exhibited a higher weight loss (nearly 71%) by these two fungi after 30 days of degradation. The borax crosslinked films exhibited 85% degradation by A.flavus. After 15 days of degradation by fungus closely related to P.daleae, the borax crosslinked films disappeared completely. This study showed that the A.flavus and fungus with close affinity to P.daleae can degrade such biocomposite films more efficiently in comparison to biodegradation in compost. © 2013 Elsevier Ltd.

DEBARATI MITRA

Chemical Technology

ANIRUDDHA MUKHOPADHYAY

Environmental Science

S MAITI

D RAY

University of Calcutta (informally known as Calcutta University or CU) is a collegiate public state university located in Kolkata, West Bengal, India.&nbsp;Within India it is recognized as a &quot;Five-Star University&quot; and accredited &quot;A&quot; Grade by National Assessment and Accreditation Council.

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The University of Calcutta has secured the Fifth position among the Universities of India in the prestigious &quot;Indian University Ranking 2019&quot; list, released by the NIRF of the Ministry of Human Resource Development, Government of India.

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It was established on 24 January 1857, and was one of the first institutions in Asia to be established as a multidisciplinary and Western-style university. Its alumni and faculty include several heads of state, heads of government, social reformers, prominent artists, only academy award winner and Dirac medal winner in India, many Fellows of the Royal Society and five Nobel laureates as of 2019 which is highest in South Asia.

University Of Calcutta

International Biodeterioration and Biodegradation

Synthetic plastics like polyolefins, acrylics which are widely used in consumer products are not biodegraded by microorganisms in the environment. The accumulation of plastics in the environment becomes a matter of great concern leading to long-term environment, economic and waste management problems. In order to overcome these problems, significant attention has been given on biodegradable polymers, and also, on the identification of microorganisms with degrading potential upon polymeric materials. Therefore, recycling and biodegradation of these polymers is an important issue for environmental protection. The present work evaluates the effect of Maleic anhydride (MA) and Methylmethacrylate (MMA) modified cellulose micro and nano fibres (MACF and MMCF respectively) on the biodegradation behaviour of Polymethylmethacrylate (PMMA)/cellulose composites. MA and MMA modified cellulose reinforced PMMA composite granules were prepared by in-situ suspension polymerization technique. PMMA/cellulose composite films were prepared by solution casting method and the biodegradation behaviour of the films was studied by soil burial method in two types of soils (Soil A and Soil B). The biodegraded films were characterized by weight loss study, viscosity average molecular weights, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and Nuclear magnetic resonance spectroscopy (NMR). The isolation and identification of the fungus, which degraded these composites, were done for the first time along with the biodegradation study with the isolated pure culture. © 2013 Elsevier Ltd. All rights reserved.

Polymer Degradation and Stability

Effect of modified cellulose fibres on the biodegradation behaviour of in-situ formed PMMA/cellulose composites in soil environment: Isolation and identification of the composite degrading fungus

The effect of crosslinkers on the biodegradation behavior of starch/polyvinyl alcohol (PVA) blend films was investigated by weight loss study, Scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). Starch/PVA films were prepared by solution casting method and 5 weight% of four different crosslinking agents like epichlorohydrin, formaldehyde, zinc oxide and borax were used in four different sets to crosslink the films. These crosslinked starch/PVA films were biodegraded in compost. Weight loss study showed that crosslinking retarded the biodegradation of the films in the first 15 days, but after that, there was a significant increase in weight loss. The DSC analysis revealed that the consumption of starch and consequent rearrangement of the PVA molecules were distinctly different in the crosslinked films due to the effect of different crosslinking agents. © 2012 Springer Science+Business Media, LLC.

Journal of Polymers and the Environment

Role of Crosslinker on the Biodegradation Behavior of Starch/Polyvinylalcohol Blend Films

Jute micro/nanofibrils (JNF) were prepared from jute by acid hydrolysis route. The jute nanofibres were characterized with the help of Transmission Electron Microscope (TEM). Starch/polyvinyl alcohol (PVA) based biocomposite films reinforced with JNF at different loading of 5, 10 and 15 wt.% were prepared by solution casting method, incorporating glycerol as a plasticizer. These biocomposite films were characterized by mechanical characterization, thermal analysis, moisture uptake behaviour, scanning electron microscopy (SEM) and atomic force microscopy (AFM). The 10 wt.% JNF loaded films exhibited best combination of properties. © 2010 Elsevier Ltd. All rights reserved.

Composites Part B: Engineering

Physico-mechanical properties of the jute micro/nanofibril reinforced starch/polyvinyl alcohol biocomposite films

The effects of incorporating different cross-linking agents into starch/poly(vinyl alcohol) (PVA) blend were examined by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), mechanical characterization, dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), moisture absorption tests, and scanning electron microscopy (SEM). Different cross-linkers such as borax, formaldehyde, epichlorohydrin, and ZnO were used to cross-link the films at the same weight percent. The films were prepared by gelatinization followed by a solution casting method. SEM microstructures revealed that the destructuring of starch granules was significantly influenced by the presence of cross-linkers during the gelatinization process. The extent of cross-linking was measured through the determination of the normalized gel mass and the normalized swelling degree of the films in dimethyl sulfoxide (DMSO) solvent. Tensile strength and tensile modulus were highest in borax cross-linked film, while the highest flexibility was achieved with the epichlorohydrin cross-linked film. Damping was remarkably increased, and moisture absorption was considerably decreased in the cross-linked films. The onset of thermal degradation was lowered, but the char yield was slightly increased in the cross-linked films. © 2010 American Chemical Society.

Journal	Data powered by TypesetInternational Biodeterioration and Biodegradation
Publisher	Data powered by TypesetELSEVIER SCI LTD
ISSN	0964-8305
Open Access	No