FROM SHRIMP SHELL TO BIOPLASTIC

Follow our Chitosan post series here:


As we left off in last week’s article, the BioPolymers series will begin tackling Chitosan in specific industries and applications, starting with BIOPLASTIC.

The plastic crisis we face needs no introduction. The photos of aquatic animals caught in plastic beer rings are heartbreaking. But the images of plastic fragments spilling out of a gutted fish evoke an immediate wave of disgust, which eventually settles into disappointment in ourselves and humanity.

As the world continues growing exponentially, so does plastic consumption – further boosted by the rise of online shopping, food delivery, and simply the ‘cheap costs’ and habits of using plastic (from coffee cups to packaging found in supermarkets) deeply ingrained in our lifestyles.

In response to this public and highly emotive problem, bioplastic players worldwide have been actively developing and commercializing various alternatives, such as PLA, PBAT, PHA and PHB. Whilst any bioplastic is a step in the right direction, common drawbacks to current bioplastic materials include its limited properties (such as tensile strength and flexibility), availability of its raw materials (better than petroleum-based but how much better?), and most importantly, its biodegradability function. What does it break down into? At what rate? And under what conditions?

I’ve set the scene and the problem in dramatic fashion, so now let’s dive into the solution.

As a multi-functional biopolymer, Chitosan is capable of being turned into bioplastic or combined with other bioplastic combinations. Last week, we talked about Chitosan’s 3Bs: BIOFRIENDLY, BIODEGRADABLE & ANTI-BACTERIAL. No matter the industry, these 3Bs follow Chitosan in every application.

Number one: BIOFRIENDLY.

Being the polymer originated from natural sources such as crustaceans, insects, fungus…, Chitosan does not create detrimental impacts on the environment when being incinerated or disposed to land or water. It is also non-toxic to all living organisms and will therefore be safe when incorporated as bioplastic.

Number two: BIODEGRADABLE.

As featured in last week’s BioPolymers article, bury any Chitosan-based bioplastic in soil and targetted Chitinase enzymes will ‘awaken’ to break down the Chitosan. The result: Not micro-plastics but natural liquid fertilizer beneficial for plants. Even better is that the biodegradability rate of Chitosan bioplastic ranges from 1 – 6 months – not 1,000 years like regular plastic. Pretty cool when you think about the idea of unpacking your groceries from your Chitosan bioplastic shopping bag and then feeding that bioplastic bag for your veggie garden to continue growing.

Figure 1: Chitosan +PBAT plastic greatly boosts BIODEGRADABILITY (as shown in the right photo)
(Source: 2020, Fabrication and Characterization of Completely Biodegradable Copolyester Chitosan Blends: I. Spectroscopic and Thermal Characterization, DOI 10.1002/masy.201650043)

Number three: ANTI-BACTERIAL.

Same explanation as last week. Given the fact being one of few natural substances with cationic/positive charge, Chitosan effectively binds with negative charges on surface of bacteria cell. From that, Chitosan can impact bacteria adversely: inhibiting metabolism & growth, breaking membrane & causing leakage of internal matters etc. and eventually, kill off bacteria.

The notion that plastic could have anti-microbial properties may have once seemed like an ‘unnecessary bonus’. However, in a world shaken up by coronavirus, there is urgent demand more than ever to reduce harmful bacteria contamination wherever and whenever possible.

Figure 2:How Chitosan destroys and wards off harmful bacteria
(Source: Interview with Chitosan experts and VNF internal research)

All in all, VNF’s bioplastic focus goes back to VNF’s company vision to sustain the world’s future. VNF is actively working with many local and global bioplastic players to develop Chitosan-based materials, notably bioplastic. Our brilliant partners aren’t just stopping at bioplastic shopping bags. Still, their applications are widespread and diverse, ranging from strong and solid construction materials, bioplastic utensils, cosmetics packaging, face masks, and even flexible film for food.

The bioplastic solution needed by the world won’t be solved overnight by one company. But VNF’s Chitosan can step up to play a significant part, either as 100% Chitosan-based bioplastic or as an additive with existing bioplastic producers (PLA, PBAT, PHA, PHB, etc.). Together, VNF’s Chitosan helps to fight bacterial contamination and boost biodegradability.

Because it’s just not shrimp co-products, VNF is saving from landfill pollution; we’re also stopping single-use plastics from heading that same way.