Plastics are generally composed of a binder and a filler. The binder is mostly resin, and the filler is a powdered or fibrous material.
Resins are generally amorphous, semi-solid or solid, high-molecular-weight organic substances that soften and deform plastically within a certain temperature range. While insoluble in water at room temperature, they are soluble in organic solvents such as alcohol and acetone.