Introduction: In the process of processing, storage, and use, the performance of plastic materials is gradually deteriorated and deteriorated when exposed to natural or artificial environmental conditions, which is what we often call plastic aging. Here are a few commonly used anti-aging methods for plastic materials, and the content is for your reference:
The structural characteristics and physical state of the polymer material itself and the external factors such as heat, light, thermal oxygen, ozone, water, acid, alkali, bacteria and enzymes received during use make it appear in the application process Performance degradation or loss, such as yellowing, relative molecular weight reduction, surface cracking of products, loss of gloss, and more serious results in a significant decrease in mechanical properties such as impact strength, tensile strength and elongation, thereby affecting the performance of polymer materials. Normal use.
This phenomenon is referred to as aging for short. Aging may occur at all stages of polymer material synthesis, storage, processing, and final application, which can lead to the end of the service life of the material and a large amount of waste, resulting in a great waste of resources and serious environmental pollution. The aging of polymer materials during use is more likely to cause huge disasters and irreparable losses.
Therefore, the anti-aging of polymer materials has become a problem that the polymer industry has to solve. At present, there are four main methods for improving and enhancing the anti-aging performance of polymer materials:
Physical protection (thickening, painting, outer composite, etc.)
The aging of polymer materials, especially photooxidative aging, first starts from the surface of the material or product, showing discoloration, chalking, cracking, and loss of gloss, etc., and then gradually penetrates into the interior. Thin products are more likely to fail earlier than thick products, so the service life of the products can be prolonged by thickening the products.
For products that are prone to aging, you can coat or coat a layer of good weather resistance on the surface of the product, or compound a layer of material with good weather resistance on the outer layer of the product, so that a protective layer is attached to the surface of the product, thereby Delay the aging process.
Improve processing technology
Many materials also have the problem of aging during the synthesis or preparation process. For example, the influence of heat during polymerization, thermal oxygen aging during processing, and so on. Correspondingly, the effect of oxygen can be mitigated by adding deoxygenation devices or vacuuming devices during polymerization or processing.
But this method can only guarantee the performance of the material when it leaves the factory, and this method can only be implemented from the source of the material’s preparation, and cannot solve the problem of aging in the process of reprocessing and use.
Structural design or modification of materials
Many polymer materials have very aging groups in the molecular structure, so through the design of the molecular structure of the material, replacing the aging groups with non-aging groups can often achieve good results.
Add anti-aging additives
At present, the effective way and common method to improve the aging resistance of polymer materials is to add anti-aging additives, which are widely used due to their low cost and no need to change the existing production process. There are two main ways to add these anti-aging additives:
(1) Direct addition method of additives
That is, anti-aging additives (powder or liquid) are directly mixed with resin and other raw materials, and then extruded, granulated or injection molded. This kind of addition method is simple and easy to implement, so it is widely used by the majority of pumping and injection molding factories.
(2) Adding method of anti-aging masterbatch
Manufacturers that have higher requirements for product quality and quality stability, more often use the method of adding anti-aging masterbatch during production.
Its application advantage is that the anti-aging additives are firstly pre-dispersed during the preparation of the masterbatch, then in the later material processing process, the anti-aging additives are secondarily dispersed, and the additives are uniformly dispersed in the polymer material matrix. The purpose of this is not only to ensure the quality stability of the product, but also to avoid dust pollution during production, making the production more green and environmentally friendly.