Common Recycled Plastics Features and Their Applications

Polystyrene waste

Polystyrene is a homopolymer of styrene, a thermoplastic general-purpose plastic, and its output is second only to polyethylene, polypropylene, and polyvinyl chloride. Polystyrene has a wide range of applications. It can be roughly divided into the following four aspects:

General Purpose Polystyrene: A large number of products for daily use as well as transparent products such as home appliances, computers, and medical supplies.

High-impact polystyrene: It greatly improves its impact strength and elongation at break. The products are widely used in electrical accessories, home appliances, food containers and so on.

Extruded Expanded Polystyrene Sheets and Thermoformed Products: Thick sheets are mainly used for thermal insulation, sound insulation, and shockproof materials. Thermoformed products are used in large quantities in food packaging and fast food containers.

Expandable Polystyrene Foam Products: Products are used for shockproof packaging of electrical appliances, insulation materials for construction, freezing and other industries.

The first two kinds of polystyrene products have long service life, and the waste thickness can be recovered by conventional recycling methods, so the pressure on the environment is also small. Afterwards, the second type of polystyrene products are mostly disposable packaging. They are bulky and consume large amounts. If they are disposed of without disposal, they will cause great pressure on the environment. A large part of what people often say “white pollution” is foamed polystyrene.

Polyethylene terephthalate waste

Polyethylene terephthalate (PET) is a polycondensation product of terephthalic acid or dimethyl terephthalate and ethylene glycol ester and is a linear thermoplastic. PET is usually a crystalline plastic, but in the bottle and film products, for its high degree of transparency, special process conditions can be used to make it amorphous.

PET has a wide range of uses due to its excellent performance, low cost, and high versatility. According to its product form, it can be divided into four categories: polyester fiber, film, engineering injection molded parts, bottles. Due to its advantages of light weight and low energy consumption, PET bottles have replaced some traditional packaging materials and have been widely used in food, beverages, cosmetics and other fields. Especially for beverage bottles, PET has taken an absolute advantage. Beverage bottles are disposable, so they are extremely wasteful.

PET bottle recycling technology has reached a very high level in foreign countries, the United States, Germany and other countries have now reached more than 80% recovery rate. Moreover, in order to facilitate recycling, these countries have also formulated some local laws and regulations that oblige the disposal, collection, use, and design of PET bottles.

Waste plastic source simple classification

Plastics, especially thermoplastics, generate waste or waste products at each stage of synthesis, molding, processing, distribution, and consumption. These are collectively referred to as “plastic wastes,” most of which are produced during consumer use, and in particular packaging. The largest amount of material, agricultural film, and disposable medicines are discarded.

The production of waste plastics:

1. Waste generated in resin production;
2. Waste generated during the molding process;
3. Waste generated during compounding and recycling processes;
4. Waste generated during secondary processing;
5. Industrial consumption of plastic waste;

The sources of such wastes and wastes are widely used and their use is complex. They must be disposed of before they can be recycled. This type of waste includes:

1) bags, barrels, etc. used in the chemical industry;
2) Containers and waste man-made filaments in the textile industry;
3) Packaging materials, foam cushions, etc. in the household appliance industry;
4) Building materials, pipes, etc. in the construction industry;
5) Shrink film, stretch film, etc. in the filling industry;
6) Turnover boxes, egg trays, etc. in the food processing industry;
7) Plastic films, greenhouse films, chemical fertilizer bags, etc. in agriculture;
8) fishing nets, floats, etc. in fisheries;
9) Bumpers, fuel tanks, and battery boxes removed from scrapped vehicles.
6. Waste plastic after consumption

China Packaging Plastics Industry Network