Silicone raw rubber ndiyo inosimbisa zvinhu zvekomboni rabha. Zvimiro zverabha yekomboni yakagadzirwa nemhando dzakasiyana dzerabha mbishi zvinosiyana
zvikuru. Zvinodiwa zveraw raw zvinosiyana pakati pemhando dzakasiyana dzekomboni rabha.Iwo ekutanga zvimiro zverabha mbishi zvinotemerwa nezviratidzo zvitatu: molar mass, vinyl zvemukati uye volatile nyaya.
Munguva yekugadziriswa, rabha yakasvibirira ine akasiyana mamolecular uremu uye vinyl zvirimo zvinowanzo shandiswa musanganiswa mune imwe chikamu. Iyo yakakwirira kuoma kwechigadzirwa, iyo yakakwirira yevinyl yemukati yerabha mbishi inodiwa. Nyaya inoshanduka inowanzodiwa kuti ive pakati nepakati (1% kusvika 2%). Kana iyo inoputika yakakwira zvakanyanya, musanganiswa werabha unonamira uye kuita kwayo kunoderera, nepo kana iyo inoputika nyaya yakadzikira, zvichave zvakaoma kuti musanganiswa werabha "utore hupfu".
Generally speaking, the higher the molar mass, the better the physical and mechanical properties of the vulcanized rubber, but its processability and fluidity will decline, and the speed of "powder intake" (filler mixing into raw rubber) will slow down. When processing molded compound rubber, raw rubber with a high molar mass (>600,000) inowanzosarudzwa. Nekudaro, kana uchigadzira zvigadzirwa zveextruded, kuti uvandudze extrusion fluidity, iyo molar mass inofanira kunge yakaderera zvishoma. Saizi yevinyl yemukati ine mhedzisiro yakakosha pakuita kwakazara kweiyo yakasanganiswa rabha. Kuita uye kuchinjika kwerabha yekomboni ine vinyl yemukati ye0.1% kusvika 0.2% ndiyo yakanyanya kunaka.