Smooth and shiny, LDPE is best for high quality printing with gloss inks. This substrate is softer than HDPE. LDPE has the most excessive branching. This causes the low density to have a less compact molecular structure which is what makes it less dense. The LDPE bags are more flexible but with less tensile strength.
So called because of its high molecular weight, HDPE is very strong. For that reason, it’s the one that’s used most commonly in supermarkets, and is instantly recognisable by its distinctive rustling sound. Although brittle, HDPE is ideal for carrying heavy loads.
Polypropylene (PP) is a thermoplastic of high clarity, high gloss, good tensile strength, excellent chemical and heat resistance. It has a higher melting point than PE which makes it suitable for applications that require sterilization at high temperatures PP is often chosen for food packaging where low permeability, heat sealing and high clarity is advantageous or required like bags for candies, cookies, herbs, nuts and other confectionaries.
A biodegradable material is NOT necessarily compostable.
A compostable material is always biodegradable.
Biodegradable refers to the ability of a substance to break down into small enough parts so that microorganisms can consume it. Biodegradable products break down naturally when placed in a land fill, if given enough time. “Bio” meaning “life”, “degrade” meaning to break down, and “able” of course meaning that it can happen.
• Breaks down into smaller sized pieces
• Requires heat, water oxygen and micro organisms but may never fully break down
• May take decades to disappear
• Plastic biodegrade into smaller pieces of plastic over a longer period of time
Compostable refers to the ability of a microbes to break down materials. Products that compost leaves no visible, distinguishable or toxic residue and generally help improve the soil. Composting is the process of recycling organic waste so that it can eventually be reused.
• Breaks down into non-toxic components
• Requires heat, water, oxygen and micro organisms to fully break down
• Breaks down completely and does not harm plant growth
• Bio based materials break down faster as long as the right condition are met