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As a biodegradable polyester, the commercialized synthesis protocol of poly(ε-caprolactone) (PCL) under mild conditions is of great significance and attractive. Herein, the ring-opening polymerization (ROP) of ε-caprolactone (ε-CL) using FeCl3 catalyst and benzyl alcohol (BnOH) as the initiator was developed. FeCl3 has been proved to be an efficient catalyst for the ROP of ε-CL under mild conditions. The conversion of ε-CL to PCL was 98.8% at 60 °C within 4 h, with number-average molecular weight (Mn) and dispersity (PDI) of 1.65 × 104 g/mol and 1.28, respectively. Moreover, a coordination-insertion ring-opening polymerization mechanism mediated by FeCl3 was proposed. Overall, this work is expected to provide a feasible industrial method for the preparation of PCL from the direct aerobic oxidation of cyclohexanone. [ABSTRACT FROM AUTHOR]

The development of a feasible industrial method for poly(ϵ‐caprolactone) (PCL) preparation is great of significant and challenging. The bulk ring‐opening polymerization of ϵ‐caprolactone (ϵ‐CL) using various organic acid catalysts and benzyl alcohol (BnOH) as the initiator was developed. Benzoic acid (BA) has been proved to be an efficient catalyst for the ROP of ϵ‐CL under mild conditions. The conversion of ϵ‐CL to PCL was 84.7 % under the optimized reaction conditions, with number‐average molecular weight (Mn) and dispersity (PDI) of 7700 g/mol and 1.25, respectively. Moreover, a monomer‐activated ring‐opening polymerization mechanism mediated by benzoic acid was proposed. Overall, this work is expected to provide a feasible industrial method for the preparation of PCL using benzoic acid as organocatalyst. [ABSTRACT FROM AUTHOR]

Considering L be a completely distributive lattice, the notion of the sum of L-convex spaces is introduced and its elementary properties is studied. Firstly, the connections between the sum of L-convex spaces and its factor spaces are established. Secondly, the additivity of separability (S-1, sub-S0, S0, S1, S2, S3 and S4) are investigated. Finally, the additivity of five types special L-convex spaces are examined. [ABSTRACT FROM AUTHOR]

In this paper, some low-level separation axioms of L-convex spaces are introduced, including S-1, sub-S0, S0, S1 and S2 separation axioms. Some relevant properties of these separation axioms are discussed. In particular, the relationships between convex spaces and induced L-convex spaces on some separation axioms are investigated. [ABSTRACT FROM AUTHOR]