Details

Autor(en) / Beteiligte

• Saito, Reiko
• Kotsubo, Hidefumi
• Ishizu, Koji

Titel

Synthesis of microspheres with ‘hairy-ball’ structures from poly(styrene- b-2-vinyl pyridine) diblock copolymers

Ist Teil von

• Polymer (Guilford), 1992, Vol.33 (5), p.1073-1077

Ort / Verlag

Oxford: Elsevier Ltd

Erscheinungsjahr

1992

Quelle

Elsevier ScienceDirect Journals Collection

Beschreibungen/Notizen

• Monodispersed microspheres with ‘hairy-ball’ structures were synthesized by crosslinking poly(2-vinyl pyridine) spherical microdomains in poly(styrene- b-2-vinyl pyridine) [P(S- b-2Vp), M ̄ n = 3.2 × 10 5 , 2Vp = 15.5 mol%] diblock copolymer film cast from 1,1,2-trichloroethane solution. The yield of the microspheres increased to 80.8 wt% with increasing reaction time. The number-average external diameter of the microspheres was 50 nm and the microspheres were stiff and truly spherical. After crosslinking, the number-average diameter of the P2Vp ball ( D ̄ n ) decreased to 24 nm from the D ̄ n of the starting block copolymer film (30.3 nm). This was due to the removal of the uncrosslinked block copolymer chains by purification of the crosslinked products. From the g.p.c. measurement with refractive index and u.v. double detected at 254 nm, the surface property of the microspheres was found to be very similar to that of PS. PS chains were expanded on the P2Vp ball, and the observed and theoretical degrees of stretching of the microsphere (1.13 and 1.12, respectively) were in good agreement.