Biologically derived plastic polymers, such as PCL, PLA, PLGA, Cellophane, , plastarch material, poly-3-hydroxybutyrate etc. are the best candidates. But they are still costlier than conventional materials.

• Polycaprolactone
• Zein, shellac – biologically derived coating materials

Dear Dariusz,

Nice question(s) and complex subject, thus different aspects are for discussion!

a) Firstly, from my point of view, the actual interest for production of biomaterials, such as biopolymers, based on natural/renewables (re)sources will continue to increase. Moreover, the extraordinary attention for new bio-alternatives will be connected to many factors including consumer demand for more environmentally sustainable products, development of biobased feedstocks, and the cumulative restrictions for the use of polymers with high “carbon footprint” of petrochemical origin, particularly in applications such as packaging, automotive, electrical, and electronics industry.

b) The rapid emergence of bioplastics is one of the major stories of the last decades, while packaging is a main field of application. Once billed as biodegradable plastics, the theme for “renewably” plastics has shifted in the recent years to sequestration of CO2 and to sustainability.

c) Here is a delicate subject for discussion “packaging produced from food, e.g. from cereals”.

I’m assuming that will be further constraints. Nowadays, other bio-based sources such as fermentable sugars from non-food cellulosic biomass, agricultural wastes, non-food crops (e.g. switchgrass), etc., are considered as further alternatives allowing carbon neutral cycles. Accordingly, new technological progress in production of biopolymers/bioplastics could be expected from the utilization and diversification of feedstocks, other than agricultural foods (e.g. instead of corn-derived dextrose).

d) Utilization of paper in packaging is an old & actual good solution to partially reduce the utilization of polymers produced from petrochemical resources (PE, PP, PET, others). On the other hand, in many applications requiring specific properties (barrier to gas and water, optical transparency, mechanical strength, etc.) the utilization of biopolymers will be a further key-direction for the development of packaging materials tailored with specific end-use properties.

e) Many projects realized by our R&D group are devoted to the production of new biomaterials/biopolymers (such as biopolyesters, e.g. polylactide) especially designed for packaging. The market for biodegradable polymers used in packaging is mounting every year, thus, important demands can be expected for those applications where biodegradability offers a clear advantage for the customers and the environment. Even that a generally recognised definition of the concept "biopolymers" does not exist, we will accept that they are mainly as follows: (a) based on renewable resources and biodegradable; (b) based on renewable resources but not biodegradable; (c) based on fossil resources and biodegradable. Bioplastics such as polylactide (PLA), polyhydroxyalkanoates (PHA), thermoplastic starch, bio-polyethylene, bio-polyamides, etc., are polymers that are made from renewable resources. Some bioplastics are also biodegradable (e.g. bio-based PLA, non-renewable polyesters such as PCL (polycaprolactone)).

f) The focus has shifted to the total “carbon footprint”, and the bio-based polymers not only can replace existing polymers in various sectors but can also provide combinations of properties for new applications. Unfortunately, for certain requests the biopolymers cannot be fully competitive with the conventional materials/thermoplastics since some of their properties are too weak. However, the development of special formulations of biopolymers (the case of PLA) is clearly in its early stages compared to the conventional polymers.

g) Connected to packaging, the level of performances, price, possibility of recyclability, environmental protection, other factors, will be decisive in selection of materials. Finally, the subject is remaining for further discussion…

Good luck in your study and best regards,

Marius

We must be very rigourous for defining biodegradability as it depends on many parameters relativee to the materials but also to the degradation conditions.

There are many points that should be taken into consideration. For example, which degradation products are generated? although in most of the cited polymers are polyesters, usually the residues like acids and others.

1. Bio - based plastics which is derived from agricultural biomass and processed and it should be degradable. which can be applied in packaging sector

Example : A replacement for polystyrene by a bio-based plastic made of mushroom

https://mushroompackaging.com/

2. Any bio-plastics , which can be compostable as per norms of EN 13432 or ASTM D6400.

3. While manufacturing bio-plastics, the use of synthetic additives (plasticizers , fillers, colorants etc) should be avoided to minimize the migration of their derivatives which are threat to environment.

4. The cost of production should be lesser than the synthetic plastic production

in the olden days glass bottles, silver utensil and cloth covers/bags used to carry the goods. why we cannot follow that to avoid such complications ?

Dear Dariusz,

in Italy some national regulations forced the use of shopping bags made of bio-plastics (moreover mater-bi), replacing PE bags, to avoid their spread in environment. The source is starch and this kind of bio-plastic is biodegradable and compostable in accordance with EN 13432.