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Vast amounts of co-streams are generated from plant and animal-based food processing industries. Efficient utilization of these co-streams is important from an economic and environmental perspective. Non-utilization or under-utilization of co-streams results in loss of potential revenues, increased disposal cost of these products and environmental pollution. At present, extensive research is taking place around the globe towards recycling of co-streams to generate value-added products. This review evaluates various co-streams from food processing industries as raw materials in developing biodegradable agricultural mulching applications. Among the agriculture-based co-streams, potato peels, tomato peels, carrot residues, apple pomace, coffee residues and peanut residues were reviewed with respect to production amount, composition, film forming components and film forming capabilities. Similarly, selected co-streams from slaughterhouses, poultry and fish processing industries were also reviewed and evaluated for the same purpose.

Using softwood pulp as the starting material, the synthesis of regioselectively substituted mixed cellulose esters with varying degree of substitution and ratio of short/long chains was successfully completed. The structures of the cellulose esters were characterised. The impact of the structural changes and the degree of substitution of the cellulose esters on thermal properties and processability were investigated. The study shows that the sequential esterification is a promising modification route for cellulose to improve its thermal processability and mechanical properties without the use of external processing aids such as plasticisers. In particular, the hexanoate group in the C6 position on the cellulose backbone acts as an internal plasticiser and improves thermal processability and increases the strength and stiffness of the cellulose ester. The properties of sequentially esterified cellulose promote its practical use in plastics, coatings, films and drug delivery. Sequentially esterified cellulose hexanoate-acetate was used successfully in a coating formulation for the preparation of tablets and showed a stable extended release profile for three water-insoluble drugs in this context. The pH of the release medium had no notable effect on the release properties.

The increasing demand for the use of sustainable materials in industrial applications has created an urge to develop technologies that enable the use of biopolymers such as cellulose for the improvement of properties of commercial products. In this study, the potential of the silyl functionalized cellulose nanofibrils (CNF) as a reinforcing additive for the water- and solvent-based two-component polyurethane (PU) lacquer coatings was evaluated. The addition of the silylated CNF improved the abrasion resistance, strength, and elasticity of the PU coatings. When using the silylated CNF as an additive, the adhesion of the PU coatings was retained. The oxygen permeation rate of the silylated CNF films was strongly influenced by the nature of the solvent. The silylated CNF showed potential as a reinforcing additive even at low loadings in the two-component PU lacquers. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 133, 44801.

In this study surface-modified nanofibrillated cellulose (NFC) was used at low levels (0.5 to1.5 wt%) as a reinforcement in a polyvinyl alcohol (PVA) matrix. The modified-NFC-PVA composite films prepared using the solution casting technique showed improved mechanical performance. Birch pulp cellulose was initially modified by allylation using a solvent-free, dry modification method followed by subsequent epoxidation of the allyl groups and finally grinding the pulp to yield epoxy-NFC. In order to obtain optimal mechanical performance, epoxy-NFC with different degrees of substitution was evaluated in the reinforcement of PVA. The addition of 1 wt% epoxy- NFC (degree of substitution, DS 0.07) enhanced the modulus, strength, and strain of pure PVA film by 307, 139 and 23 %, respectively, thus producing the best performing film. The results demonstrate the favourable effect of chemically functionalized NFC on the mechanical properties of polyvinyl alcohol compared to unmodified NFC as reinforcement. In order to improve industrial and economic feasibility, the manufacture of the composite was also done in situ by grinding cellulose directly in PVA to produce the new biocomposite in a one-step process.

In this study chemically surface-modified nanofibrillated cellulose (NFC) was used at low levels (0.5 to 3 wt%) as reinforcement in a polyvinyl alcohol (PVA) matrix. The modified NFC-PVA films prepared by a solution casting technique showed improved mechanical performance and good optical properties. NFC was allylated and further epoxidised with hydrogen peroxide. The addition of 1 wt% epoxy-NFC enhanced the modulus and strength of the pure PVA film, 474% and 224%, respectively. This composite film exhibited visible light transmittance of 83%. The results also showed that 1 wt% epoxy-NFC loading was beneficial to improve the crystallinity of PVA. SEM characterization confirmed better dispersion of modified NFC within the PVA matrix compared to unmodified NFC. The result showed the favourable effect of chemically modified NFC on the mechanical properties of PVA compared to unmodified NFC as reinforcement.

Polystyrene (PS, 1), polycaprolactone homopolymers (PCL, 2) and 3-Iodo-2-propynyl n-butylcarbamate (IPBC, 3) were physically mixed in dichloromethane (DCM) and processed into solid microspheres by using emulsion solvent evaporation method. Five different compositions with varying PS/PCL ratio were tested. The phase morphology of the microspheres was studied using Phase imaging atomic force microscopy (AFM) of polished cross-sections. Scanning electron microscopy was utilized to assess the distribution of IPBC in the polymer microspheres. The phase separation of the PS and PCL polymers in solvent cast films was assessed using polarized light optical microscopy of 11 polymer blends (0-100 wt-% PCL in PS). The PS/PCL-IPBC microspheres were incubated in water at RT and the release of IPBC was studied using high performance liquid chromatography (HPLC) at time points 1, 7 and 30 days. The microspheres dispersed in water borne outdoor paint matrix were tested for their antifouling activity against moulds in vitro.

The VTT-Aalto-FIOH-IST joint RESCOAT (Novel Responsive Surfaces based on Active Hybrid Coatings Utilizing Encapsulation Technologies) project focuses on the development of novel active and responsive surfaces based on paint and thin coatings with encapsulated active agents. The developed polymeric or silica capsules are either slowly releasing or responsive to the external stimulus. The active agents in the capsules may have different functionalities being e.g. flame retardants, biocides, self-healers, antifreezers. By combining and further developing the existing know-how of coating and encapsulation technologies, the project aims to provide feasible functional solutions against e.g. biofouling, flare-up (delayed), wearing and scratches (self-healing) or ice nucleation. The developed coating and encapsulation technologies increase competitiveness of the products especially in the fields of construction, processing, electronic devices, machinery, infrastructure and transportation.

In the present work, we describe the procedure for neat synthesis of polystyrene (PS) microcapsules and PS capsules containing different amounts of the biocide (3-iodo-2-propynyl N-butylcarbamate, IPBC). We have used phase separation and solvent evaporation techniques for producing the PS microcapsules. The preparation of PS microcapsules was performed in the aqueous medium containing surface active molecules. During evaporation of the organic solvent, hard and round-shaped PS microcapsules were formed. The diameter of the PS microcapsules varied between 55-63 micrometers determined by laser diffractometer. The study comprises characterization of the microcapsules with and without biocide using different techniques. The presence and the amount of encapsulated IPBC were determined by SEM-EDS and HPLC technique. The release of the encapsulated IPBC into water from the micro-sized PS microcapsules was determined. The knowledge obtained from this study can be utilized in the development of active and protective anti-fouling surfaces