Solvent cementing techniques can readily join many thermoplastics. A variety of solvents are available, and when used correctly they can provide bond strengths of up to 100 percent that of the plastic substrate. However, their effect on the plastic substrate can range from little or none to completely ruining a part, depending on the plastic and the solvent.
Solvent cementing basically involves softening the bonding area of the plastic substrate with a solvent formulation, assembly the mating surface together under slight pressure, and allowing sufficient time for the solvent to dissipate from the joint area. In this way, the solubilized plastic substrate, in effect, becomes a thermoplastic adhesive.
This article will review the common solvent cement formulations, the process variables that are critical, and the factors that must be considered when using this assembly technique. The physical and chemical characteristics of specific thermoplastics will also be noted as they can have a significant effect on the outcome.