Addition polymerization is a type of chain-growth polymerization where monomers add to one another in a sequential manner, without the loss of any atoms. The process typically involves three main steps: initiation, propagation, and termination. The resulting polymer has the same elemental composition as the monomer. Common examples include polyethylene (from ethylene) and polypropylene (from propylene).

加成聚合是一种链式增长聚合，其中单体按顺序相互添加，而不损失任何原子。该过程通常包括三个主要步骤：引发、增长和终止。所得聚合物具有与单体相同的元素组成。常见的例子包括聚乙烯（来自乙烯）和聚丙烯（来自丙烯）。