Overview Recycled plastic is the reuse of plastic. After the mechanical blade crushing operation, the plastic is reused. Recycled plastic refers to the plastic raw materials recovered by processing and processing waste plastics through physical or chemical methods such as pretreatment, melt granulation, and modification, and is the reuse of plastics.

* Usage

Plastic has good processing properties and is easy to form, such as: blowing, extrusion, pressing, easy cutting, and easy welding. Many plastics can be granulated in production and life, such as waste food bags, sandals, wires, wire boards, agricultural films, tubes, barrels, basins, packing belts, and various waste plastic products can be repeatedly formed and processed into plastics. Raw materials, after special processes and formulas, are used to manufacture machine parts and components; can be used to make water pipes, agricultural machinery, packaging bags, cement bags; can replace some wooden products; can be used to make various plastic bags, buckets, pots, toys And other plastic products, daily necessities.

Recycled plastics and granulated plastics have broad prospects, turning waste into treasure. The products (plastic granules) are sold very widely. The demand for plastic companies is large. A medium-sized agricultural film factory needs more than 1,000 tons of polyethylene granules each year, and a medium-sized shoe factory annually. Needs more than 2,000 tons of PVC particles, small individual private enterprises, the annual demand of particles is also more than 500 tons, so the plastic particle gap is too large to meet the needs of plastic manufacturers, therefore, the sales are excellent and the benefits are extremely high good. There are a wide range of raw materials for waste plastics. Some people have waste plastics, which are easy to purchase and cheap in price (this is true everywhere). A city consumes more than 10 tons of plastic products such as plastic food bags every day. There are also a lot of waste plastics in rural areas that can be recycled The particles don't worry about selling.

* Performance Changes

PVC: Discoloration is more obvious after regeneration. It will have a light brown color after one-time regeneration extrusion, and almost opaque brown color after three times. The specific viscosity does not change at the second time, and there is a tendency to decrease after more than two times. Regardless of whether it is hard or soft PVC, stabilizers should be added during regeneration. In order to make the recycled products shiny, ABS1%-3% for blending can be added during regeneration.

PE: After the regeneration of PE, the performance has decreased, the color turns yellow, and after multiple extrusions, the viscosity of high density polyethylene decreases, and the viscosity of low density polyethylene increases.

PP: During the first regeneration, the color is almost unchanged, the melt index increases, and the melt index is still increased after more than two colors are aggravated. After regeneration, the breaking strength and elongation have decreased, but there is no problem in use.

PS: The color turns yellow after regeneration, so the regenerated PS generally performs color difference. The degree of decline in the properties of recycled materials is proportional to the number of regenerations. There is no significant change in the breaking strength when the blending amount is less than 60%, and there is no significant change in the limiting viscosity when the blending amount is less than 40%.

ABS: Discoloration is more significant after regeneration, but there is no significant change in performance when the blending amount does not exceed 20-30%.

Nylon regeneration also has the problems of discoloration and performance degradation, and the blending amount is preferably less than 20%. The regenerated elongation decreases, but the elasticity tends to increase.

* Distinguish good from bad

1. Look at the color:The lighter the color (even colorless and transparent), the wider the range of use and the higher the level. Such as white, it can be adjusted to a variety of other colors, and can also be returned to white products, the same price is also high. Secondly, because of the needs of the product, various ingredients are added to the raw materials.

2. Look at CaC03 (stone powder) content. The more CaC03 content and the lower the grade, the lower the price. From the naked eye, the product is not bright, dull (except matt), the content of CaC03 will be more, and it will feel heavy in the hand. If it is burnt with fire, the burned part will turn red and become gray. In addition, we should pay attention to the reinforced (referred to as glass fiber) products. The available reinforced products are only PA, PBT, PP and so on, and the prices are not high. There are several kinds of alloy materials. At present, there is only one type of ABS+PC in domestic market, and the others are not. According to the specific gravity (density) of the raw materials, it can be judged whether the intermixed materials can be reused. At present, the most problematic problems are the intermixing of ABS and PS, the intermixing of PC and PMMA, the PVC flakes (bottles) and PEl, and the flakes. Mixed, PE and PP are semi-intermixed. After these materials are intermixed, it is difficult to use because of the similar density.

3. Look at the nature of recycled plastic materials. The purer the material, the higher the grade; the impure material, the lower grade, and some intermixes are not even required.

4. Difference from waste plastic. Waste plastic directly crushes plastic products into powder or granules, and can still distinguish what materials are, such as injection molding, wire drawing, or film. Recycled materials are recycled. I don’t know how many times I can’t accurately distinguish something. I can only classify them according to the number of cycles. At the very least, they are divided into special grades, first grades and second grades.

* Four points of reference for the price evaluation of the recycled plastics market

Price evaluation of recycled plastics

1. Color and performance of recycled plastics Generally speaking, the lighter the price of recycled plastics, the better the price. The closer the performance is to the new material, the better the price. The better the performance index, the better.

2. The purity of recycled plastic The higher the purity of recycled plastic, the better, except for modified materials, because modified materials mainly depend on performance indicators; the compatibility of each component in recycled materials can also be included in this point, the better the compatibility The higher the price.

3. The appearance of recycled plastics first depends on the shape of the pellets. The better the shape of the pellets, the higher the price. The second is whether it is foamed, layered, whether the hardness meets the requirements, whether the color is uniform, whether the gloss is good, etc. .

4. Application of recycled plastics The use, processing characteristics, wide range of applications and other special requirements of recycled plastics will affect the valuation of recycled plastics.