What are bioplastics?

Bioplastic that is biobased is made partially or wholly from raw materials derived from renewable biological sources, these include products and by-products from agriculture that are rich in carbohydrates, especially saccharides such as grain, sugar beet, sugar cane, etc. The biobased content could derive from different raw materials such as polymers, fillers, plasticizers or additives.

Biobased VS Biodegradable

There can sometimes be confusion between the terms biobased and biodegradable, biodegradability and biobased content are in fact, two distinct features of bioplastics.

A common misconception is that biobased bioplastics are all biodegradable, they are not. A bioplastic that is biobased may not necessarily be biodegradable, and a biodegradable bioplastic may not be biobased.

We can therefore categorise bioplastics in three groups, each with their own set of properties and characteristics.

Biobased plastics: a plastic where at least a part of the content comes from renewable biological or agricultural materials

Biodegradable & biobased plastic: a plastic that is designed to degrade under compost conditions. Containing renewable content

Biodegradable plastics: a plastic that is designed to degrade under compost conditions. Based on fossil resources

Dryflex Green TPE compounds are biobased

Why use biobased?

Sustainability: plastics are predominantly a by-product of oil, a diminishing resource. Biobased plastics help to reduce the usage and dependency on limited fossil resources, which are also expected to become more expensive in the coming decades. We are therefore seeing increasing demands to look at how we can work with biobased, renewable materials and bring new opportunities for sustainability.

Improved carbon footprint: plants absorb carbon dioxide from the atmosphere as they grow. By using these crops to create biobased plastic products, greenhouse gases (CO2) are removed from the atmosphere.

Life cycle assessment: utilising raw materials that are derived from renewable vegetable crops, that are responsibly grown, can contribute to an improved LCA (Life Cycle Assessment), which measures the environmental impact of all stages a product’s life from cradle to grave.

Ethical land management: crops for industrial use can be grown in poor soil which is unsuited to food crops, thereby avoiding food crop displacement and improving biodiversity.

Consumer demand: purchasing power favours products from sustainable resources.

Creating soft materials with high levels of renewable content:

Since most biobased raw materials in the market are quite hard on their own, a major challenge has been to develop compounds with high renewable content, low hardness while at the same time maintaining mechanical properties at acceptable levels.

As can be seen in Figure 1 on the next page, the Dryflex Green TPE compounds divert from the other soft thermoplastic materials on the market today by including also soft materials with high levels of renewable content and thereby covering a greater segment and opening up more design possibilities.

Figure 1 : Percentage of Bio-content vs Hardness

A look even closer to nature

The biobased content in the Dryflex Green compounds can derive from various raw materials such as polymers, fillers, plasticizers or additives. For applications wanting a look even closer to nature, we have also developed compounds using organic fillers and natural fibres from plants, crops or trees, including cork. These give an additional ‘organic’ appearance

Cork is a natural product which comes from the bark of the cork oak tree. The removal of the bark does not harm the trees and the bark is only harvested after the first 20 years of growth. The removal stimulates a steady regeneration of the bark.

How do they compare to conventional TPEs

Dryflex Green TPE compounds display mechanical and physical properties close to and comparable to TPE compounds from fossil based raw materials.

In general the Dryflex Green compounds show very good bonding behaviour to PE and PP.

We have also developed special grades with good bonding to ABS, PET and PLA.

Like conventional TPE compounds, Dryflex Green TPEs can easily be coloured to give vibrant and appealing visual impact.

Typical properties of representative Dryflex Green grades

Customized building blocks

As requirements can vary greatly for each application, we see a need for highly customised formulations.

Rather than a standard grade range, we have therefore qualified a number of raw materials which will allow us to work with a modular system to build a compound that is tailored to customer specifications.

Depending on requirements regarding bio content and hardness, food contact grades are available.

Customization options

·        • Percentage and type of renewable content (to over 90% ASTM D 6866)

·        • Hardness (20 Shore A to 50 Shore D)

·        • Adhesion to polymers, such as PE, PP, ABS, SAN, PET & PLA

·        • Colour • Filled or unfilled compounds

·        • Compounds with organic fillers and natural fibres to give an additional ‘organic’ appearance

·        • Mechanical behaviour such as flexibility and tensile properties

·        • Price level

·        • Surface finish & haptics

·        • UV and heat stability

Key Properties
Dryflex Green TPE compounds display mechanical and physical properties comparable to TPE from fossil based raw materials

·        Flexibility & tensile properties

·        Soft-touch feel

·        Suitable for injection moulding & extrusion

·        Adhesion to polymers, such as PE, PP, ABS, SAN, PET and PLA

·        Fully recyclable

·        Can easily be coloured

·        Amounts of renewable content to over 90% (ASTM D 6866)

·        Hardnesses from 15 Shore A to 55 Shore D

Applications
Dryflex Green TPE compounds can be used in many applications that currently use conventional TPE compounds, such as soft-touch grips and handles, sealing and closures for packaging, sports equipment, toys and infant care, soft-touch areas for packaging.

Dryflex Green TPE compounds could open up sustainability options in the consumer, automotive, packaging, medical and construction markets

Processing
Dryflex Green TPE compounds can be processed using conventional thermoplastic fabricating methods, including injection moulding and extrusion.