In:
Polymer Chemistry, Royal Society of Chemistry (RSC), Vol. 14, No. 19 ( 2023), p. 2344-2354
Abstract:
The development of living/controlled polymerization technologies is of great importance in both fundamental studies and in industrial applications. Herein, we report for the first time the use of easily synthesized phosphonium ylides Ph 3 P = CR 1 R 2 (R 1 ,R 2 = H,H (P-ylide-1), H,Me (P-ylide-2), H,Et (P-ylide-3), H,Ph (P-ylide-4), Me,Me (P-ylide-5)) as the Lewis base (LB) in the Lewis pair polymerization (LPP) of (meth)acrylates. The P-ylide-2–P-ylide-5/Al(C 6 F 5 ) 3 , P-ylide-1–P-ylide-5/AlR(BHT) 2 (R = Me, Et, i Bu; BHT = 2,6- t Bu 2 -4-MeC 6 H 2 O), and P-ylide-1–P-ylide-5/Al i Bu 2 (BHT) systems are all highly effective initiators of methyl methacrylate (MMA) polymerization, of which the P-ylide-2/AlMe(BHT) 2 system is the best for living/controlled polymerizations, resulting in high initiation efficiencies ( I * 〉 90%). The relative Lewis acidities of the Lewis acids (LAs), Al(C 6 F 5 ) 3 , AlR(BHT) 2 , and Al i Bu 2 (BHT), are evaluated using the Gutmann–Beckett method whilst the basicity of the P-ylides is evaluated through natural bond orbital computations. Model reactions using the P-ylides, LAs, and MMA were accomplished, and revealed that the active species in the MMA polymerization, the enolate Ph 3 PCH(Me)CH 2 C(Me)C[OAlMe(BHT) 2 ](OMe) ( 〉 99%), is efficiently generated. Furthermore, homopolymerizations and block copolymerizations of MMA, ethyl methacrylate, benzyl methacrylate, n -butyl methacrylate, n -butyl acrylate, and ethylhexyl acrylate were successfully realized using the P-ylide-2/AlMe(BHT) 2 system.
Type of Medium:
Online Resource
ISSN:
1759-9954
,
1759-9962
Language:
English
Publisher:
Royal Society of Chemistry (RSC)
Publication Date:
2023
detail.hit.zdb_id:
2528812-X
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