| Share | Phrase |
| 21.00% | radical [completeness] initiator |
| 9.26% | free-radical initiator |
| 7.65% | free [cost] initiator |
| 5.64% | photopolymerization initiator |
| 5.21% | add initiator [perform operation] |
| 4.55% | polymerization initiator |
| 3.76% | initiator addition |
| 3.55% | unreacted [state] initiator |
| 3.26% | azo initiator |
| 3.21% | initiator presence |
| 2.80% | anionic [physical/chemical] initiator |
| 2.49% | initiator react |
| 2.28% | initiator to mixture |
| 2.22% | initiator proportion |
| 2.20% | use initiator [perform operation] |
| 2.16% | reset initiator |
| 2.14% | lithium initiator |
| 2.05% | initiator feed |
| 1.77% | plug initiator |
| 1.50% | initiator actuation |
| 1.37% | preferred [effectiveness] initiator |
| 1.14% | ignition initiator |
| 1.01% | initiator time |
| 0.99% | amount initiator |
| 0.93% | actuate initiator [perform operation] |
| 0.88% | activate initiator [perform operation] |
| 0.76% | initiator [does] include |
| 0.74% | suitable [effectiveness] initiator |
| 0.59% | employ initiator [perform operation] |
| 0.57% | initiator [does] cause |
| 0.52% | reduce initiator [perform operation] |
| 0.50% | initiator [does] have |
| 0.43% | include initiator [perform operation] |
| 0.38% | provide initiator [perform operation] |
| 0.33% | have initiator [perform operation] |