Cellulose filaments as sustainable packaging materials: Enhancing barrier properties with cationic starch and alkylketene dimer

Single-use plastic packaging has become a serious problem for many countries, including Canada, with millions of tons consumed annually without considering end-of-life impact. Researchers are developing sustainable alternatives to non-biodegradable plastic. While cellulose microfibers (MFC) and nanocrystalline cellulose (NFC) are common raw materials for film production, their preparation requires costly chemical treatments that cause environmental pollution. Kruger Inc. developed a method to produce cellulose filaments (CFs) with high fibrillation using only mechanical treatment. This study uses CFs to produce packaging films through handsheet forming, with cationic starch (CS) and Alkylketene Dimer (AKD) as additives for enhanced water, water vapor, and oxygen resistance. We analyzed morphological, barrier, mechanical, and optical properties using various techniques, including SEM, WVTR, WVP, OTR, contact angle, Cobb 60, burst index, tensile index, tear index, and transmittance. The films showed promising properties, with WVTR decreasing to 49.42 g/m²·day, WVP to 2.82 × 10^-6 g·m/m²·day·Pa, OTR to 3.3 cc/m²·day, and Cobb value to 32.2 g/m². After adding 3 % CS, films demonstrated good mechanical performance with a tensile index of 80.49 N·m/g, burst index of 10.93 kPa·m²/g, and tear index of 0.66 mN·m²/g. These results prove CFs' effectiveness with CS and AKD in forming films with excellent properties. CFs show potential compared to other biopolymers due to their eco-friendliness and cost-effectiveness. The production method is simple, scalable, and yields biodegradable films composed of biomass-derived materials.