This research investigated a non-thermal, dielectric-barrier discharge (DBD) plasma-based approach to prepare poly(acrylic acid) (PAA) from acrylic acid in its liquid state at atmospheric temperature and pressure. Neither additives nor solvents were needed, and the polymerization was accomplished both as a film and inside a sheet of mesoporous paper. All prepared samples were characterized and the DBD plasma-initiated kinetics were analyzed for the polymerization of acrylic acid. Using FTIR semi-quantitative analysis, the degree of polymerization was monitored, and the reaction followed an overall second-order kinetic model with respect to the DBD-initiated polymerization. Additionally, the application of a PAA-modified paper as a water retention cloth or ‘wet wipe’ was investigated. The results showed that the PAA-modified paper substrates using DBD plasma increased water retention as a function of plasma treatment time.

The chemical treatment of wood has been shown to increase its mechanical strength by forming composites with a variety of polymers. Polyethylene glycol diacrylate (PEGDA) has commonly been used as a polymer reinforcement to increase the strength and resistance of spruce wood for various applications, such as protection from weathering. In this study, PEGDA was impregnated into wood samples and polymerized by dielectric barrier discharge (DBD) plasma to form wood–polymer composites (WPCs). The kinetic rate order of PEGDA was explored using FT-IR quantitative analysis and the DBD plasma-initiated polymerization was determined to be second order. The strength of the wood samples was then determined by a three-point flexural test. The PEGDA-treated spruce wood samples showed improved flexural strength versus the untreated wood samples. The WPCs were also made using a UV treatment method and were then compared to the DBD plasma-treated samples. The results showed that the DBD plasma-treated samples yielded superior flexural strength relative to the UV-treated samples. We accredited this difference in strength to the plasma process and its ability to penetrate into the various layers of the wood and initiate polymerization, as opposed to UV light that can only penetrate superficially, initiating polymerization in only the first few layers of the wood surface.

Herein, a comprehensive investigation is carried out to explore several gel and composite materials and the techniques that can be used to produce enhanced materials with superior mechanical properties. This thesis focuses on different but related projects, separated by chapters. In Chapter 1, a quick overview of what defines gels and composites, as well as various examples of each are given. Additionally, the types of polymerization tools available for forming these materials are explored and their mechanical properties are discussed. In Chapter 2, a hydrogel is studied that was made using a uniquely synthesized double network system to produce a highly stretchable, injectable, re-moldable, and strong gel with strain sensing capabilities. In Chapter 3, a novel inorganic-based gel composite made from a truly 1-dimensional titanate is investigated. The investigation of this recently discovered material led to the elucidation of a previously unknown gelling mechanism rarely seen for inorganic materials. The compressive strength of the gels was measured, and the chemical composition of the material was determined. In Chapter 4, a wood-polymer composite (WPC) was produced using a non-conventional method of polymerization called dielectric-barrier discharge (DBD) plasma. The DBD plasma-treated method was compared to a similar WPC made using UV light as the polymerization technique. The DBD plasma technique produced superior WPCs with higher flexural strength than the UV-treated WPCs. Finally, an acrylic acid paper composite is produced and tested as a wet wipe material to determine its anti-drying properties. This composite was also produced using the DBD plasma technique for the bulk polymerization of the acrylic acid-immersed paper sheets.