Functionalization of Oligosiloxane for Polyester Comonomer.

This paper proposes a new functionalized oligosiloxane as a comonomer for polyester, designed to provide hydrophobic surface properties and enhance low-temperature impact resistance. The functionalization of polymer resin itself has attracted attention in the context of monomaterialization. Chemically designing the primary structure of not only polymers but also monomers is crucial for enhancing the intrinsic performance of the resin. However, little is known about oligosiloxane monomers for polyester that can provide oligosiloxane-like properties such as hydrophobicity and flexibility at low temperatures. Here, we report the functional design of a polyester material through silicone copolymerization. A novel comonomer was designed and synthesized to optimize both the molecular structure and the compatibility of the silicone segments, promoting uniform copolymer formation. Incorporating silicone into the polymer matrix reduced surface energy, thereby improving water repellency. Furthermore, the flexibility imparted by the silicone components effectively mitigated the brittleness of polyester at sub-zero temperatures, resulting in superior impact resistance. Structural analysis, contact angle measurements, and low-temperature impact tests were conducted on the copolymers. The results confirmed that optimizing comonomer design enables significant enhancement of both hydrophobicity and impact durability, contributing to the development of high-performance polyester materials suitable for demanding environments.