PAPER COATING FORMULATED WITH MICROFIBRILLATED CELLULOSE, NATURAL RUBBER AND PECTIN FOR ENHANCED BARRIER PERFORMANCE

Paper coating formulated with microfibrillated cellulose, natural rubber and pectin for enhanced barrier performance.

B. P. M. Ramasini^a, D. B. Silva^a, J. S. Bernardes^a

^aBrazilian Nanotechnology National Laboratory, CNPEM, Brazil

([email protected], www.lnnano.cnpem.br)

Paper usage in packaging is an environmentally friendly alternative to conventional plastics, as it is a biodegradable and recyclable material. However, paper has low barrier properties to oil, gases, and water vapor, which limits its use. Microfibrillated cellulose (MFC) has emerged as a green alternative to enhance the barrier properties of paper, demonstrating excellent resistance to oxygen, grease, and mineral oils but showing poor resistance to water and water vapor¹. This study presents the development of a straightforward one-pot method for depositing a blend of MFC and natural rubber latex (NRL) in the presence of pectin to improve the barrier properties of paper. First, the combination of MFC and NRL in water demonstrated inadequate stability, negatively affecting its performance as a coating. However, the addition of pectin significantly enhanced the dispersibility and colloidal stability of the mixture, resulting in a more uniform formulation. To evaluate the barrier properties of papers coated with the blend, we tested water vapor transmission rate (WVTR at 23°C and 50% relative humidity) and grease resistance. Applying a single coating layer reduced the WVTR by more than eight times, decreasing it from 732 to 88 g.m^-². day^-1. Additionally, the coated paper demonstrated significant resistance to oil and grease, achieving the maximum rating in the barrier test kit (kit rating of 12). This study led to the development of a colloidally stable formulation, offering excellent barrier properties and a sustainable packaging solution.

Keywords: Coating, cellulose, barrier, blend, paper.

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