Methods of joining polymers using ultrasonic energy

This invention relates in general to methods of joining materials such as polymers, and in particular to methods of joining polymers using ultrasonic energy. In a method of joining a solidifiable liquid polymeric material to a solid material to produce a solid article, the solid material is contacted with the liquid polymeric material at an interface. Ultrasonic energy is applied so that the energy reaches the interface between the contacting solid material and liquid polymeric material. A joint is formed at the interface by allowing or causing the liquid polymeric material to solidify, to produce a solid article comprising the solidified polymeric material joined to the solid material.