Fiber reinforced composites are typically prepared using thermosetting polymeric resins derived from petroleum resources and involving hazardous chemicals. We present a vinyl-ester system utilizing a 100% renewably based polyester enabling the sequestration of carbon from the atmosphere into durable goods for decades. The biopolymer poly(meso-lactide) (PML) is synthesized using a strategy giving vinyl end groups. In place of potentially carcinogenic styrene which is predominantly used as a reactive diluent to reduce the thermoset viscosity, the new sustainable bioresin dissolved in methyl methacrylate (MMA), infused into various fibers, and cured to form the composite panels. Mechanical properties are excellent and comparable with less sustainable materials from fossil resources. As homeowners adopt a lifestyle that is more responsive to environmental need, industry and academia are tasked with finding more sustainable solution for cast polymer products like countertops and sinks. Particulate fillers in the cast polymers are bound by either poly(methyl methacrylate)/methyl methacrylate (PMMA/MMA) or unsaturated polyester/styrene (UPR/Styrene) resin. For the first time ever, we have introduced biopolymer poly(lactide) (PLA) dissolved in MMA as a novel bioresin formulation which can be directly substituted for less sustainable PMMA/MMA and more carcinogenic UPR/Styrene counterparts. Mechanical properties of fabricated biorenewable solid surface and cultured marble composites are on par with commercially available products. This environmentally benign resin is also used to fabricate a prototype of a Drop-in-Bowl solid surface and preliminary calculations show a 24% reduction in greenhouse gas emissions (CO2 equivalent) compared to PMMA/MMA acrylic resins available in the market. Otherwise destined to landfills or incineration, recovery and recycling of composite materials not only improves the sustainability metrics but also opens the door to various end-of-life options. Recycling of sinks and countertops via solvolysis reduces the usage of new resources, prevents waste, and lowers the emission associated with their production and transportation. For the first time ever, Drop-in-Bowl solid surface sink was fabricated using fully recyclable resin PLA dissolved in MMA and is demonstrated that simple base solvolysis can be employed to recover the particulate filler material along with other end-of-life options including edible food ingredient, and superabsorbent polymer. Chain transfer agents (CTAs) are conventionally used to regulate the polymer molecular weight during the free radical polymerization of acrylate polymers. Also, curing reaction of MMA undergoes a sudden temperature rise because of auto-acceleration known as Trommsdorff effect. These curing effects in the presence and absence of CTAs were investigated for MMA resin-based systems. One-dimensional (1D) mathematical model combining the reaction kinetics and heat transfer was extended to incorporate the effect of CTAs. Agreement between experimental findings at small scale (6 to 8 g) and simulation results indicate that in bulk polymerization of MMA based resins, presence of chain transfer not only controls the polymer properties but is also reduces the peak polymerization temperatures. Also, control of the in-situ polymerization of thick methacrylic composite parts is essential to minimize or avoid the monomer boiling. Above mentioned thermokinetic model was expanded considering of spatial geometry and experimentally validated to study the effect of CTAs to mitigate the temperature rise during ~kg quantities of bulk free radical polymerization and fabrication of thick MMA/PMMA resin composites.
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