Technical Analysis of Packaging Industry: Modified Plastic

Anything that can improve the original properties of the resin through physical, mechanical and chemical effects can be called plastic modification. The meaning of plastic modification is very broad. During the modification process, both physical and chemical changes can achieve it.

The commonly used methods of plastic modification are as follows:

1. Add modified substances

a. Add small-molecule inorganic or organic matter

Inorganic additives like fillers, reinforcing agents, flame retardants, colorants and nucleating agents, etc.

Organic additives including plasticizers, organotin stabilizers, antioxidants and organic flame retardants, Degradation additives, etc. For example, Topfeel add degradable additives to some PET bottles to accelerate the degradation rate and degradability of plastics.

b. Adding polymer substances

2. Modification of shape and structure

This method is mainly aimed at modifying the resin form and structure of the plastic itself. The usual method is to change the crystal state of the plastic, crosslinking, copolymerization, grafting and so on. For example, styrene-butadiene graft copolymer improves the impact of PS material. The PS is commonly used in the housing of TVs, electrical appliances, ballpoint pen holders, lampshades and refrigerators, etc.

3. Compound modification

The composite modification of plastics is a method in which two or more layers of films, sheets and other materials are combined together by means of adhesive or hot melt to form a multi-layer film, sheet and other materials.In the cosmetic packaging industry, plastic cosmetic tubes and aluminum-plastic composite tubes are used in this case.

4. Surface modification

The purpose of plastic surface modification can be divided into two categories: one is directly applied modification, the other is indirectly applied modification.

a. Directly applied plastic surface modification including surface gloss, surface hardness, surface wear resistance and friction, surface anti-aging, surface flame retardant, surface conductivity and surface barrier, etc.

b. The indirect application of plastic surface modification includes the modification to improve the surface tension of plastics by improving the adhesion, printability and lamination of plastics. Taking electroplating decorations on plastic as an example, only the coating fastness of ABS can meet the requirements for plastics without surface treatment; Especially for polyolefin plastics, the coating fastness is very low. Surface modification must be carried out to improve the combination fastness with the coating before electroplating.

The following is a set of fully shiny silver electroplated cosmetic containers: Double wall 30g 50g cream jar, 30ml pressed dropper bottle and 50ml lotion bottle.