With the growing concern of the adverse effect of countless non-biodegradable and non-renewable materials, a great deal of momentum to counteract this effect is prevailing from all levels of stake-holders of the society. As of 2020, about three-fourth (73.8%) of the world textile fiber consumption is comprised of man-made fibers with a constant growing demand . Since the synthetic fibers are non-biodegradable and coming from non-renewable resource, they lead an unsustainable cycle of production and consumption. In addition, the environment concern and long-term economic goal have raised an appreciable impetus to think about environment friendly composite materials. In this regard, cellulose based composite materials have attracted the ample attention towards the researchers of the world. Although there exist a number of different variety of biomass and organic materials for example grass, agricultural crops, and wood or wastes are significant renewable resources. Among them, cellulose is the most abundant and ubiquitous natural polymer in the eco-system [2–4]. The worldwide cellulose production is approximately 1012 tons per annum [5–7]. Due to some novel attributes such as renewability, biodegradability, nontoxicity, and improved mechanical properties, low thermal expansion, low density and light weight cellulose can be applied in the field of pharmaceutical, medical, biomedical, construction, automotive, cosmetic and packaging industries [8–11]. Traditionally, cellulose is extracted from the wood which contains only 45% cellulose [2, 5]. The other non-woody fibers such as hemp, sisal, flax, though contain higher amount of cellulose, these fibers are less important in terms of economy and world production . In this context, jute fiber is the attractive and competent alternative for cellulose as it has higher amount of cellulose (⁓75%) content and second most economical crop in the world next to cotton [12, 13–15]. Several attempts have been deployed to extract micro-nanocellulose from jute fiber. The prominent examples are acid hydrolysis , steam explosion [17, 18], TEMPO mediated oxidation  and oxidation with ammonium persulfate . Among them APS oxidized cellulose contain carboxylic functional moieties due to the direct oxidation in the C6 position of the glucose ring of the cellulose chain [20, 21].
Polyvinyl alcohol (PVA) is water-soluble and colorless synthetic resin. Due to presence of hydroxyl groups, PVA shows excellent film-forming capability by creating intermolecular hydrogen bond [22, 23]. The barrier, mechanical and thermal properties of PVA film can be improved by reinforcing filler materials like cellulose , titanium , collagen , carbon nanotubes , silica , chitosan , and so on. An overarching goal of this research is to develop a composite film of PVA reinforced with microcrystalline cellulose obtained from jute fiber by single step APS oxidation method. The carboxylated MCC from jute fiber cross-linked with PVA through ester linkage or intra and inter molecular H-bonding resulted the improved thermal properties of the composite films at an elevated temperature. In this study the surface topography, surface chemistry and thermal properties of MCC and PVA-MCC composite films were investigated. The knowledge gathered from this study might lead the applicability of this PVA-MCC composite at different conditions.