This document specifies four methods for the determination of the content of the following groups of organic peroxides used as rubber vulcanizing agents. There are three titration methods and one gas-chromatography method.

a)       titration method A for group a: Peroxyketals:

1,1-Di(tert-butylperoxy)cyclohexane (DTBPC; CAS Registry Number^®:3006-86-8)

1,1-Di(tert-butylperoxy)-2-methylcyclohexane (DBPMC; CAS RN 147217‑40‑1);

1,1-Di(tert-butylperoxy)-3,3,5-trimethylcylcohexane (DBPTC; CAS RN 6731‑36‑8);

2,2-Di(tert-butylperoxy)butane (DBPB; CAS RN 2167‑23‑9);

Butyl −4,4-di(tert-butylperoxy)valerate (BPV; CAS RN 995‑33‑5);

b)       titration method B for group b: Diacyl peroxides:

Dibenzoyl peroxide (CAS RN 94‑36‑0);

Di(2,4-dichlorobenzoyl) peroxide (CAS RN 133‑14‑2);

Di(4-methylbenzoyl) peroxide (CAS RN 895‑85‑2);

c)        titration method C for group c: Diaralkyl and alkyl-aralkyl peroxides:

Di(tert-butylperoxyisopropyl)benzene (CAS RN 2212‑81‑9);

Dicumyl peroxide (CAS RN 80‑43‑3);

tert-Butyl cumyl peroxide (CAS RN 3457‑61‑2);

d)       gas-chromatography for dialkyl peroxides, using a capillary or packed column.

2,5-Dimethyl-2,5-di(tert-butylperoxy)hexane (CAS RN 78‑63‑7)