Paper is envisioned
as an alternative to plastics in certain applications
to overcome the problems associated with the excessive use of plastics.
Water and oil repellency is one of the key requirements for many packaging
applications. However, the existing water and oil repellent paper
products have poor biodegradability and are also difficult to recycle.
Here we have reported an inexpensive approach for preparing recyclable
water and oil repellent paper products using biobased materials such
as starch and zein. The application of dual-layer coatings of starch
and zein onto a Kraft paper yielded a “Cobb 60” value
of 4.81 g/m2. In addition, the coated paper exhibited excellent
grease resistance with a kit rating of 12/12. Scanning electron microscopy
characterization confirmed that the dual-layer coating filled the
pores of the paper substrate. The mechanical properties, as well as
the thermal stability of the paper, were maintained after the coating
treatments, and thus this coated paper has potential for widespread
use in our daily lives while also minimizing the environmental footprint
of packaging materials.
Coated paper substrates
are used for a wide range of applications.
The biggest challenge that remains unsolved with regard to coated
paper is its recyclability. Herein, we report a unique approach that
relies on 100% biobased and biodegradable food-safe materials for
water- and oil-resistant papers. A 35-liner paper was coated with
an oil-resistant chitosan solution and subsequently by a hydrophobic
zein solution. The resultant chitosan–zein-coated paper showed
remarkable water resistance (Cobb 60 value of 4.88 g/m2) and oil repellency (kit rating 12/12). Scanning electron microscopy
(SEM) analysis was used to determine the changes in the surface texture
of the paper before and after coating treatment. The excellent mechanical
properties of the coated paper were retained after the coating treatment.
In addition, the pulp was recycled from the chitosan–zein-coated
paper to validate the recyclability of this novel approach.
Reported herein is an economical, plastic-and fluorine-free coating approach for oil and water repellent paper substrates using blends of poly(vinyl alcohol) and chitosan-graft-polydimethylsiloxane copolymer. The obtained coated paper showed good water-resistance, as evidenced by its low Cobb60 values of 20 ± 2.1 g/m 2 and high water contact angles of 119 ± 6.3. The kit rating of the coated paper was 7.6/12, indicating decent grease-resistant properties as compared to the kit value of 0/12 for the uncoated paper. The coated paper is also repulpable as demonstrated by the complete washing off the coating from the coated paper. Giving the cost-effective nature of the coating materials and good water and oil-resistant properties of the coated paper, the approach developed here is commercially viable, and will offer a multitude of environmental benefits such as the elimination of microplastic-and PFAS problems associated with existing paper coatings.
An increase in the environmental and health concerns over fluorochemicalbased, wax-based, and extrusion-based paper coatings has led to a growing interest in bio-based, biodegradable, and repulpable alternatives to obtain water-and oil-repellent coatings. Reported herein is a fluorine-free, plastic-free, and costeffective water and grease resistant paper coating approach that utilizes blends of corn-starch (S) and a novel chitosan-graft-polydimethylsiloxane (CP) copolymer. The hydrophobic and oleophobic performance of the S/CP-coated paper was evaluated by varying the ratio of S and CP in the overall blend. The S/CP-coated papers were observed to have low cobb60 values (water absorptivity) of 13 ± 0.9 g m −2 and an excellent kit rating (oil resistance) of 12/12. The S/CP-coated paper substrate surface profile was analyzed via scanning electron microscopy (SEM). The repulpability of the coated paper is also demonstrated by washing the coating materials from the paper and recovering the pulp.
Heteroleptic catalyst stability toward disproportionation was modelled based on ligand donor abilities, which is of critical importance in some catalyses.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.