1, according to the modified target selection of additives

 

According to the target of modification, appropriate additives should be selected, adding additives should be able to give full play to their effects and reach the required indexes. Indicators are generally national standards of products, international standards, or special indicators put forward by customers. The following is in order to make the plastic has a special performance need to add additives, additives selection of the reference opinions are:

 

(1) toughening - adding elastomers, thermoplastic elastomers and rigid toughening materials;

 

(2) Reinforcement -- adding glass fiber, carbon fiber, whisker and organic fiber;

 

(3) flame retardant - add bromine (common bromine and environmental bromine), phosphorus, nitrogen, nitrogen/phosphorus composite expansion flame retardant, antimony trioxide, hydration metal oxide and other flame retardants; Of course, the flame retardant is not as general, and the material structure must have a certain match. Also consider the thermal decomposition of the material to select the corresponding flame retardant, otherwise it may cause waste;

 

(4) antistatic - add all kinds of antistatic agent;

 

(5) conductive - adding carbon (carbon black, graphite, carbon fiber, carbon nanotube), metal fiber and powder, metal oxide;

 

(6) magnetic - add ferrite magnetic powder, rare earth magnetic powder including samarium cobalt (SmCo5 or Sm2Co17), NdFeB (NdFeB), samarium iron nitrogen (SmFEN), aluminum nickel cobalt magnetic powder three categories;

 

(7) heat conduction -- adding metal fibers and powders, metal oxides, nitrides and carbides, carbon materials such as carbon black, carbon fiber, graphite and carbon nanotubes, semiconductor materials such as silicon and boron;

 

(8) Heat resistance -- adding glass fiber, inorganic fillers, heat resistance agents such as substituted maleimides and β-crystal nucleating agent;

 

(9) transparent - adding nucleating agent, for PP, α-crystal nucleating agent sorbitol derivative series of products Millad 3988 has the best effect

 

(10) wear-resistant - PTFE, graphite, molybdenum disulfide, copper powder, etc.;

 

(11) Electrical insulation -- adding calcined kaolin, etc.;

 

(12) insulation - add mica, montmorillonite, quartz, etc.

 

 

2, additives and resin to match

 

The selection of additives should be targeted, and the varieties with good modification effect on resin should be selected. Such as:

 

(1) Red phosphorus flame retardant is suitable for PA, poly butyl terephthalate (PBT), poly ethyl terephthalate (PET);

 

(2) Nitrogen flame retardant is suitable for engineering plastics containing oxygen, such as PA, PBT, PET, etc.;

 

(3) Glass fiber has good heat-resistant modification effect on crystalline plastics, but poor effect on non-crystalline plastics;
 

(4) carbon black in the crystalline resin effect is good.

 

 

Of course, the thermal oxygen aging of resin in the processing process can not be ignored, we need to add antioxidants. The long-term storage of the material during the aerobic process also requires the addition of corresponding antioxidants. Outdoor products in order to ensure long-term material properties also need to add anti-aging additives such as weather resistance, light stability. Dispersants, lubricants, compatilizers and so on are materials must be mastered, but sometimes it is appropriate to add.