Surface- and Bulk-Modified Galactoglucomannan Hemicellulose Films and Film Laminates for Versatile Oxygen Barriers

Abstract

The objective of this study was to create oxygen barrier films based on the hemicellulose O-acetylgalactoglucomannan (AcGGM) that show high resistance toward moisture-rich conditions. We have applied Williamson benzylation, a classic derivatization method of carbohydrates, as well as two different methods for surface grafting, and, finally, lamination of unmodified hemicellulose films with the synthesized hydrophobic benzylgalactoglucomannan (BnGGM). It was found that the thermoplastically behaving BnGGM could form independent transparent and strong films that were easy to handle. As expected, their resistance toward water was very high, and the oxygen barrier properties showed drastically lower sensitivity toward moisture than films from the corresponding unmodified material. The surface grafting and lamination methods were approached in order to try and combine excellent barrier properties with moisture tolerance. It was found that the grafting methods applied had a positive effect in this direction; however, lamination turned out to be an even more promising option.

Separation of Galactoglucomannans, Lignin, and Lignin-Carbohydrate Complexes From Hot-Water-Extracted Norway Spruce by Cross-Flow Filtration and Adsorption Chromatography

“…According to Thornton et al (1994); about 10% of the GGM in softwood is dissolved. The high solubility of GGM is due to its high degree of acetylation in combination with its relatively low-molar-mass (Hartman et al 2006), which is also the case for hot-water-extracted GGM. describes a process where 5 kg acetyl-galactoglucomannan is recovered per ton of thermomechanical pulp.…”

“…Examples of uses are hydrogels (Lindblad et al 2001) and gas barrier films for food packaging produced with the hardwood abundant xylan (Grondahl et al 2004) and softwood abundant galactoglucomannans (GGM) (Hartman et al 2006). Besides the three common components of wood (cellulose, hemicellulose, and lignin), wood composition investigations of dissolved wood have also found lignin covalently bound to sugars (Bjorkman 1954;Koshijima et al 1984;Azuma et al 1981;Lawoko et al 2006).…”

Utilization of wood cell wall components

“…Galactglucomannan is another target to develop hemicellulose-based hydrogels [30], film laminates for oxygen barriers [31], cationized material [32], and multifunctional macroinitiator for single-electron transfer-mediated living radical polymerization [33].…”

Biopolymer Coatings for Paper and Paperboard

“…Hence, general coating formulations used by the industry do not constitute potential barriers, as these require more binders and lower pigment loads beneath the paraffin wax, shellac resins). Water-resistant bioplastics can also be produced from blends of thermoplasticized starch with biodegradable polymers such as polycaprolactone using compatibilizing agents, known as Mater-Bi Ò products, and through use of microbial polymers (e.g., poly(3)-hydroxybutyrate, known as Biopol Ò and discussed in Chapter 4) or polylactic acid-based polymers discussed in Chapter 3 (e.g., Ecopia Ò , Lacea Ò ) [20,[40][41][42][43][44].…”