New alternatives to single‐use plastics: Starch and chitosan‐ graft ‐polydimethylsiloxane‐coated paper for water‐ and oil‐resistant applications

Technoeconomic Analysis for Biodegradable and Recyclable Paper Coated with Synthetic Ionic PBAT for Packaging Application

This study presents a technoeconomic analysis (TEA) for a novel ionic polybutylene adipate-co-terephthalate (PBAT), CPBAT, as a paper coating material, showcasing excellent water and oil resistance. This TEA determined total capital investment, operating costs, and minimum selling prices for a production capacity of 1,000 kg of CPBAT per day. The minimum selling prices of CPBAT coated on Kraft paper (CPBAT-K) and CPABT coated on starch-coated Kraft paper (CPBAT-S) are estimated to be $1.327/m2 and $1.864/m2, respectively. Additionally, the results of a sensitivity analysis show that the production of CPBAT-K and CPBAT-S is highly sensitive to the production capacity, raw material costs, energy efficiency of the coating process, reaction energy, and reaction yield. Recovery of the ionization solvent only marginally increases the selling prices of CPBAT-K and CPBAT-S, and hence, it is highly favorable. By increasing production capacity, lowering raw material costs, using energy-efficient coating machines, and partially recovering energy from reactions, the prices of CPBAT-K and CPBAT-S can be reduced to $0.588/m2 and $0.914/m2, respectively. Given that commercial polyethylene-coated paper prices range from $0.94/m2 to $1.850/m2, CPBAT-based coated papers with comparable mechanical and barrier properties along with biodegradability and recyclability are positioned as highly competitive and sustainable alternatives in the market.

Polycaprolactone/Starch/Agar Coatings for Food-Packaging Paper: Statistical Correlation of the Formulations' Effect on Diffusion, Grease Resistance, and Mechanical Properties

Paper is one of the most promising materials for food packaging and wrapping due to its low environmental impact, but surface treatments are often needed to improve its performance, e.g., the resistance to fats and oils. In this context, this research is focused on the formulation of a new paper bio-coating. Paper was coated with liquids containing poly(hexano-6-lactone) (PCL), glycerol and variable percentages of starch (5-10% w/w PCL dry weight), agar-agar (0-1.5% w/w PCL dry weight), and polyethylene glycol (PEG) (5% or 15% w/w PCL dry weight) to improve coating uniformity and diffusion. A design of experiments approach was implemented to find statistically reliable results in terms of the best coating formulation. Coated paper was characterized through mechanical and physical properties. Results showed that agar content (1.5% w/w PCL dry weight) has a beneficial effect on increasing the resistance to oil. Furthermore, the best coating composition has been calculated, and it is 10% w/w PCL dry weight of starch, 1.5% w/w PCL dry weight of agar, and 15% w/w PCL dry weight of PEG.

Prevention of marine biofouling in the aquaculture industry by a coating based on polydimethylsiloxane-chitosan and sodium polyacrylate

In this study, a series of novel hydrophobic/hydrophilic hybrid (HHH) coatings with the feature of preventing the fouling phenomenon was fabricated based on polydimethylsiloxane (PDMS), as matrix and two hydrophilic polymers: chitosan and sodium polyacrylate, as dispersed phases. Antibacterial activity, pseudo-barnacle adhesion strength, surface free energy, water contact angle, and water absorption were performed for all samples. Evaluating field immersion of the samples was performed in the natural seawater. The results showed that the dispersed phase containing PDMS coatings showed simultaneously both of antibacterial activity and foul release behavior. Among the samples, the PCs4 coating containing 4 wt% Cs indicated the lowest pseudo barnacle adhesion strength (0.04 MPa), the lowest surface free energy (18.94 mN/m), the highest water contact angle (116.05°), and the percentage of fouling organisms 9.8 % after 30 days immersion. The HHH coatings can be considered as novel eco-friendly antifouling/foul release coatings for aquaculture applications.

Evaluation of Coatings to Improve the Durability and Water-Barrier Properties of Corrugated Cardboard

Recently, corrugated cardboard furniture gained interest from the market, yet is limited to indoor application. With an aim toward outdoor usage, water-barrier improvement of such products must be achieved. In this work, three commercially available coating grades (i.e., polymeric, mineral-filled polymeric, and hybrid silica sol-gel products) were spray-coated on corrugated cardboard using a facile, yet readily transferable, process. The investigation assessed the coating performance from the different drying conditions and natural UV-vis weathering effects, characterising their water absorption, hydrophobicity, coating morphology, and colour change. Results show a reduction in water absorption values (up to −98%) for both the polymeric coatings; instead, the hybrid sol-gel coating showed contact angles up to almost 150°. Generally, the SEM micrographs displayed some surface defects as well as good thickness homogeneity. A perceivable colour change occurred for each sample (CIEDE2000 up to 6.41), mainly occurring in the 0–100 h time range. This work provides promising results for the outdoor application of corrugated cardboard furniture.