The radiation-induced polymerization of the optically active monomer (1S,5S)(−)-β-pinene was studied in presence of olivine (composition of the selected sample: (Mg0.91 \(\cdot\) Fe0.09)2SiO4), which is a ubiquitous rock-forming mineral in terrestrial, planetary, meteoritic, interstellar and circumstellar dust and astronomical geominerals. A reference study was also conducted on the radiation-induced polymerization of (1S,5S)(−)-β-pinene under inert atmosphere and without any additive. The polymerization kinetics rate constants and the radiation chemical yield were determined for both series of samples (without and with olivine) using thermogravimetry (TGA), gravimetry and polarimetry as analytical techniques. Olivine plays an evident role in triggering a higher radiation chemical yield (Gp) in the synthesis of poly(β-pinene) (PβP) at initial and at lower doses with respect to the reference pure (1S,5S)(−)-β-pinene polymerization. The PβP undergoes a grafing reaction on olivine and the maximum grafted amount was reached at 1000 kGy with 6.12% by weight over olivine. The chemisobed PβP fraction on olivine was found at 34.5%, while the remaining 65.5% of PβP loaded on olivine was found toluene soluble and extractable. The spectropolarimetry of the PβP extracted from the olivine surface suggests considerably lower molecular weight than that observed on the PβP synthesized in the bulk monomer.
