This study presents the development of advanced agarose-based semi-interpenetrating polymer networks (semi-IPN) incorporating cross-linked functional methacrylic copolymers to overcome the limited mechanical performance and structural stability of conventional agarose matrices. A library of thirty-one copolymers was synthesized by reversible addition−fragmentation chain-transfer polymerization (RAFT), atom transfer radical polymerization (ATRP), iron-mediated ATRP, photoinduced electron-transfer RAFT (PET-RAFT), or activators regenerated by electron transfer ATRP (ARGET-ATRP) using 2-hydroxyethyl methacrylate (HEMA), oligo(ethylene glycol) methacrylate (OEGMA), and 2–(N,N–dimethylamino)ethyl methacrylate (DMAEMA) as primary monomers, and furfuryl methacrylate (FMA) or vinyl methacrylate (VMA) as cross-linkable co-monomers. Polymerization outcomes depended strongly on monomer composition and synthetic route: RAFT was particularly effective for OEGMA-rich systems, ATRP for DMAEMA-containing copolymers, and PET-RAFT for VMA-based materials. Four selected copolymers were subsequently cross-linked through Diels–Alder (DA), thiol–ene, or combined covalent–ionic strategies, yielding stable hydrogels with tunable responsiveness. Three copolymer systems were successfully integrated into agarose matrices, resulting in different semi-IPN with substantially enhanced mechanical reinforcement, with improvements of 150- to 1330-fold relative to controls. The OEGMA-based, DA-cross-linked system exhibited the strongest overall reinforcement, while its DMAEMA counterpart (covalent and ionically cross-linked) showed the most pronounced relative enhancement over its corresponding agarose-free hydrogel. Scanning electron micrographs revealed homogeneous, well-defined, interconnected microporous structures, and thermorheological tests confirmed temperature-responsive behavior in the DA-based systems. Overall, this work establishes a versatile synthetic strategy for constructing degradable, mechanically robust, and biomedically relevant agarose-based semi-IPN with potential in tissue engineering, wound healing, and drug delivery.
Transforming highly hydrophobic monomers into polymers via miniemulsion polymerization offers a compelling, environmentally friendly alternative to toxic organic solvents by combining monomer-rich nanodroplets with a water-based continuous phase, thereby enabling efficient heat transfer, reduced costs, solvent recovery, and industrial scalability. This study demonstrates the application of both supplemental activator and reducing agent atom transfer radical polymerization (SARA ATRP) and its surface-initiated variant (SI-ATRP) in miniemulsion systems. The research confirms the ability to conduct SARA ATRP with limited oxygen presence without additional degassing agents. Most importantly, interfacial and ion-pair catalysis SI-ATRP was used for flat surface modification in heterogeneous media for the first time, unlocking the opportunities of grafting hydrophobic polymer brushes in environmentally friendly conditions. The novel technique enabled fully controlled, linear and rapid growth of thick layer of polymer chains from silicon wafers resulted in poly(n-butyl acrylate) (PnBA) brushes up to 193 ± 2 nm in only 0.5 h and poly(tert-butyl acrylate) brushes over 230 nm in 1 h. Block copolymer brushes were furthermore synthesized and characterized using time-of-flight secondary ion mass spectrometry (ToF-SIMS) depth profiling to demonstrate the block architecture of Si-g-PtBA-b-PnBA-b-PtBA. Considering environmental aspects, the surface modifications via SI-ATRP were also conducted at room temperature or without degassing the reaction system, obtaining polymer brushes over 50 nm in thickness. Through the presented approach, the use of an aqueous solution for material functionalization with hydrophobic polymers was not only implemented, but the laboratory scale scale-up modification without the need for elevated temperature or deoxygenation was also demonstrated.
This study proposes a ternary strategy integrating elastic fiber–rich byproducts from meat industry, polymeric materials, and plant-derived components to develop an innovative composite membrane material. Polymerizable deep eutectic solvent (PDES) was employed simultaneously as a monomer, functional composition, and penetration enhancer in “one-stone-several-birds” way. Subsequently, sixteen PDES–animal issue composite membranes were fabricated via UV-induced polymerization by varying the types of tissues, composition ratios, and the amount of guar gum as crosslinker. They showed remarkable swelling capacity (up to 190.17%), high porosity (up to 39.14%), superior water vapor transmission (>2900 g/m2·day), and excellent mechanical strength (tensile stress up to 1.09 MPa). For more funtionalization, the ideal samples were chosen for loading Lophatherum gracile leaf powders, and the excellent properties provide support for their use as a universal material in various fields such as raw material preservation, healthcare, pharmaceuticals, and so on.
