The way to improve the properties and qualities of some polymers is the addition of certain materials that we will call additives, which give them a certain particularity according to their nature:

• Carbon Fibers: consistency and thermal resistance, the most influential additive in a polymer
• Fiberglass: termal resistance, flexibility
• Aramid fibers (Kevlar): basis of bulletproof vests, high resistance to shocks and impacts
• Ceramic: rigidity and hardness, cons it is abrasive
• Mica flakes: electrical insulating and high hardness
• Basalt: high thermal conduction, electrical insulator
• Carbon nanotubes: electrical conductivity
• Graphene: in its oxide form with antimicrobial power and also in nanotubes

• other polymers, for example ABS+PC, in specific proportions: mix their qualities
• Metal: rigidity, thermal resistance