Nanotechnologies / Materials
Plastics, Packaging materials, Consumer goods

Development of marine biodegradable bioplastics based onstarch
Division of Applied Chemistry, Graduate School of Engineering
Associate Professor Yu-I Hsu

https://researchmap.jp/yuihsu

Professor Hiroshi Uyama

https://researchmap.jp/read0168389

Nanotechnologies / Materials

Abstract
Plastic has enriched our daily life with its excellent properties
such as low cost, lightweight, and design adaptability. However,since most plastics do not biodegrade in the natural environment,
marine plastic garbage has come serious as a social problem inrecent years, and countermeasures are urgently needed. We havestudied marine biodegradable biomass plastics by blending starchwith biodegradable plastics. Developed polysaccharide composite/blended plastics, promoted the practical use of polysaccharide
blended plastics equipped with a switching function that induces
marine biodegradability, and achieved significant improvements inheat resistance and impact resistance of bioplastics.

pare starch based marine biodegradable plastics with improved
mechanical properties by introducing hemiacetal crosslinking has
not yet been reported, and could be a paradigm shift for the development of socially important biodegradable materials. It is very
interesting not only from the point of view of functional material development, but also from the perspective of industrial developmentin the environmental field that contribute to global conservation.

▍ Background & Results
Since most plastics are petroleum-derived and do not biodegrade in the natural environment, marine plastic garbage has attracted attention as a major social problem. Marine biodegradable
plastics that can be used as a countermeasure are limited to someof aliphatic polyesters, and in addition to low production volumes
compared to general-purpose plastics, they are also expensive.
Starch is abundant in nature, cheaper than common petroleum-derived plastics or aliphatic polyesters, and suitable for industrial
production. Also, although starch is not generally considered amarine biodegradable plastic, it is inherently a marine biodegradable polymeric material. Therefore, in this research, we used starch
as a raw material to create a marine degradable plastic material
that has a low environmental impact throughout its life cycle. By
compounding starch with cellulose nanofibers, the disadvantage
of starch, such as water resistance and mechanical strength, canbe improved. Recently, we have started a marine biodegradable
bio-based plastics (MBBP) development platform, which enables
a variety of moldings by blending biodegradable plastics such aspoly(lactic acid) and poly(butylene succinate) with thermoplasticstarch (TPS). We are aiming to develop MBBP, prepared using TPS
from cassava starch, and prototypes were developed by various
molding methods. The developed MBBP has (1) biodegradability,(2) physical properties comparable to common plastics, (3) pricecompetitiveness, and (4) thermoplasticity that enables a wide
range of plastic moldings. The spread of MBBP in society is expected to contribute to resource recycling and circular economy
through the active use of biomass, and to solve the problem ofmarine plastic garbage by incorporating marine biodegradation
functions into plastic products.

Prototypes of starch-CNF composite

MBBP prototypes▍ Significance of the research and Future perspective
This technique provides an alternate pathway to alleviating theproblem of marine plastic garbage, and could be possibly usefulfor single-use applications in different fields such as packaging,healthcare, and agriculture. Furthermore, a new method to pre-Marine biodegradable starch-CNF composite

P a t e n t Japanese Patent No. 4942436, Japanese Patent No. 5057874, Japanese Patent No. 5495360
Soni, Raghav; Hsu, Yu-I; Uyama, Hiroshi. Synergistic effect of hemiacetal crosslinking and crystallinity on wet strength of cellulose nanofiber-reinforced
Tr e a t i s estarch films. Food Hydrocoll., 2021, Vol. 120, pp. 106956 (1-10). doi: 10.1016/j.foodhyd.2021.106956
http://www.chem.eng.osaka-u.ac.jp/~uyamaken/
UR
L http://www.chem.eng.osaka-u.ac.jp/mbbp/
https://www.kyu-gs.com/
K e y w o r d bioplastics, biomass plastics, marine biodegradable plastics, starch, cellulose