Plastic shopping bags are polyolefin as the main raw material, the appropriate addition of other materials made of packaging materials. The main products include low-density polyethylene or high-pressure polyethylene (LDPE), high-density polyethylene or low-pressure polyethylene (HDPE), linear low-density polyethylene (PE), commonly known as soft, LLDPE) and metallocene polyethylene (mLLDPE) four categories. In order to reduce its costs, most companies have joined about 30% of calcium carbonate filled with plastic shopping bags, such plastic shopping bags due to incineration in the garbage dump when the release of toxic gases. Just introduced the national plastic shopping bag standard plastic shopping bags are divided into the following three categories:
Ordinary plastic shopping bags - the use of polyolefins and fillers as raw materials, such plastic shopping bags do not have degradation performance, abandoned in the wild will not be degraded. Such plastic shopping bags have excellent recyclability, can be recycled several times. The performance of the recovered material is slightly reduced to a different degree, but it can be used for shopping bags or garbage bags where the performance requirements are not high and the color requirements are not strict. The key question is whether the problem can be recovered.
Starch-based plastic shopping bags - these shopping bags with modified starch as the main raw material, the appropriate addition of a small amount of other biodegradable materials to improve its performance. The plastic shopping bags are discarded in use after the field can be naturally degraded.
Degradable plastic shopping bags - these shopping bags to fully degradable plastic as raw materials, with complete degradation performance. Product abandonment in the wild can be completely degraded into small molecules of microorganisms, without any environmental pollution, foreign to promote such plastic shopping bags. In accordance with the specific composition of completely degradable plastics can be divided into the following three categories:
(1) PLA, PHA biodegradable plastics synthesized by bio-fermentation with natural starch as raw materials require considerable consumption of food, so the development space is limited.
(2) the use of carbon dioxide as raw material synthesis of aliphatic polycarbonate (APC) degradation of plastic, which is shouting the industrial by-product of carbon dioxide as raw material, neither the consumption of food, but also reduce the emissions of carbides, Eliminate greenhouse gas caused by global warming phenomenon, serve two purposes, so the market prospects.
(3) in the ordinary plastic to add non-starch degradation agent of the complete degradation of products, in the industrialization stage, such as the degradation of reliable performance, very promising.
Non-woven shopping bags are made of plastic non-woven fabrics, many people think that cloth is a natural material, and in fact is a misunderstanding. Commonly used non-woven raw materials for polypropylene (English referred to as PP, commonly known as polypropylene) or polyethylene terephthalate (English referred to as PET, commonly known as polyester), especially PP with plastic bags with the same PE, are Five general-purpose plastic varieties, are 50 years can not be degraded plastic varieties. Such as we are known as the green shopping bags of ordinary non-woven shopping bags, is made of polypropylene fiber with a special process, in essence, polypropylene (PP) for the typical varieties of plastic, also belong to plastic bags, so environmental And ordinary plastic shopping bags, also can not be completely degraded.
From the specific cost-effective speaking, under the same conditions, the strength of non-woven bags as plastic bags, and not waterproof, the price is higher than the plastic bags as much as several times. Need to mention is the use of more than two kinds of materials made of non-woven shopping bags, recycling more difficult than ordinary plastic shopping bags.
We all know that the strength of paper and water resistance are not good, a lot of water-based products such as seafood can not packaging, heavier metal products are difficult to load. First, the raw materials for the production of paper mainly wood, the world's forest resources is extremely scarce, which is the greatest waste of environmental resources; followed by the process of making paper will produce a lot of water pollution, paper mills across the country, such as crossing mice, beaten everywhere. Therefore, a large number of paper bags is the largest waste of environmental resources, the largest environmental pollution.
Cotton and linen shopping bag strength is better than paper bags, can be recycled several times, but the water resistance is not good. The advantages of cotton and linen shopping bags can be recycled, but the bag dirty how to do? Washing is the most commonly used method, but the water is wasted water resources, with phosphorus-containing detergent will pollute the soil, while ordinary washing and can not kill bacteria.
1, for the general dry goods, it is recommended to use the United States waste or European waste, in accordance with A or B grade kraft liner board technical indicators to control the production of base paper. The surface can be noodles, you can not noodles, which should be based on whether to print complex patterns and advertising. The weight of the paper can be 135 ~ 150 g / m2.25 × 20 × 15cm paper bag to bear the weight of up to 8 ~ 15 kg.
2, for the need to bear a certain amount of water goods, you can also use the whole waste paper. But on the basis of the above criteria, add a certain wet strength agent 0.5 ~ 1.0%, wet strength can reach 10 ~ 15% dry strength can be.
3, for meat or other wet goods, the same can be used to create all the waste paper shopping bags. This requires the addition of paper in the process of paper or the surface coated with environmentally friendly anti-oil agent. It is also possible to spray the water-soluble or degradable resin twice on a kraft liner with good surface strength.
4, many manufacturers in mainland China, has been developed all the waste paper clip paper. That is, in the papermaking, the two layers of pulp between the textile principle of adding water-soluble yarn, the kind of paper layer can reach the strength of four layers of kraft paper, can completely replace the ordinary cement bag paper. Similarly, single-layer paper can be used on shopping bags.
5, these products are safe, environmentally friendly.