TY - JOUR

T1 - Evaluation of paper coated with cationic starch and carnauba wax mixtures regarding barrier properties

AU - Santos, Allan de Amorim dos

AU - Matos, Lays Camila

AU - Mendonça, Maressa Carvalho

AU - Lago, Rafael Carvalho do

AU - Muguet, Marcelo Coelho dos Santos

AU - Damásio, Renato Augusto Pereira

AU - Ponzecchi, Andrea

AU - Soares, Jenaína Ribeiro

AU - Sanadi, Anand Ramesh

AU - Tonoli, Gustavo Henrique Denzin

N1 - Publisher Copyright: © 2023 Elsevier B.V.

PY - 2023

Y1 - 2023

N2 - Studies of single-use packaging have aimed to replace materials obtained from non-renewable sources with biodegradable materials from renewable sources in response to environmental concerns. Their barrier properties maximize shelf life and product safety. To provide such green packaging, this work aimed to describe the chemical, physical, morphological, and barrier properties of bilayer coatings made from mixtures of cationic starch (S) and carnauba wax (W) on kraftliner paper (86 ± 1 g/m²). Two coating layers (15.0 ± 0.5 g/m²) of both materials in different proportions were compared to uncoated paper and doublewet-and-dry paper. The addition of cationic starch to carnauba wax raised the melting point of the wax, preventing it from completely entering the paper's pores but instead producing a layer on top of them. The hydroxyl groups present in coated paper S contributed to its hydrophilicity, showing a high Cobb value, absorbing 153 g/m² more water than control samples. Further, the mixtures showed higher hydrophobicity than the cationic starch-treated samples, with a high-water contact angle (100 ± 4°), similarly found for the W treatment. In addition, mixtures showed 0.35°/s less wettability than the W treatment. In terms of mechanical strength, the lower tensile strength and Young's modulus of the coated sheets brought on by hornification appear to have been predominantly caused by water in the suspensions. The addition of carnauba wax to the cationic starch decreased the resistance of coated papers to oil. However, there was an improvement in the water barrier by decreased water absorption and wettability and an increase in water contact angle.

AB - Studies of single-use packaging have aimed to replace materials obtained from non-renewable sources with biodegradable materials from renewable sources in response to environmental concerns. Their barrier properties maximize shelf life and product safety. To provide such green packaging, this work aimed to describe the chemical, physical, morphological, and barrier properties of bilayer coatings made from mixtures of cationic starch (S) and carnauba wax (W) on kraftliner paper (86 ± 1 g/m²). Two coating layers (15.0 ± 0.5 g/m²) of both materials in different proportions were compared to uncoated paper and doublewet-and-dry paper. The addition of cationic starch to carnauba wax raised the melting point of the wax, preventing it from completely entering the paper's pores but instead producing a layer on top of them. The hydroxyl groups present in coated paper S contributed to its hydrophilicity, showing a high Cobb value, absorbing 153 g/m² more water than control samples. Further, the mixtures showed higher hydrophobicity than the cationic starch-treated samples, with a high-water contact angle (100 ± 4°), similarly found for the W treatment. In addition, mixtures showed 0.35°/s less wettability than the W treatment. In terms of mechanical strength, the lower tensile strength and Young's modulus of the coated sheets brought on by hornification appear to have been predominantly caused by water in the suspensions. The addition of carnauba wax to the cationic starch decreased the resistance of coated papers to oil. However, there was an improvement in the water barrier by decreased water absorption and wettability and an increase in water contact angle.

KW - Green packaging

KW - Kraft paper

KW - Kraftliner packaging

KW - Palm tree wax

KW - Sustainable coating

U2 - 10.1016/j.indcrop.2023.117177

DO - 10.1016/j.indcrop.2023.117177

M3 - Journal article

AN - SCOPUS:85165360750

VL - 203

JO - Industrial Crops and Products

JF - Industrial Crops and Products

SN - 0926-6690

M1 - 117177

ER -