Organic coatings are used in multiple applications, many we are aware of, such as paints and some most people are unaware of such as in aluminum interior can coatings.  For the sake of clarity, all the coatings discussed in this series will be organic-based and may be referred to simply as “coatings.”  Coatings are generally grouped into four main categories [1]. The first ... [Click to Continue...]

The previous post described the chemistry and formulations using Recyclamine® hardeners.  This post will discuss the process to chemically remove the cured network from the glass fabric reinforcement. Dubey et. al., describes the details of a formulation specifically designed for wet lay-up resin transfer molding RTM [1]. The recyclable RTM formulation was used to produce ... [Click to Continue...]

The previous five posts discussed the end-of-life considerations using thermosets with covalently adaptive networks termed vitrimers.  The next two posts will cover the chemical degradation approach to thermoset recycling.  As shown schematically in Figure 1, there are multiple approaches to degrade fully cured thermoset networks. Figure 1. Schematic of chemical ... [Click to Continue...]

In previous posts, the chemistry, and viscoelastic properties of vitrimers were presented.  This post will discuss how vitrimers can be used in production to form thermoset parts/composites that can be reprocessed at end-of-life. For a network that contains covalent adaptive networks, as the temperature increases, exchange reactions such as transesterification in epoxy ... [Click to Continue...]

The previous post described the work of Liebler [1] who showed both epoxy carboxylic acid networks and epoxy anhydride networks contained covalent adaptive networks that underwent transesterification reactions at elevated temperatures (i.e. vitrimers). The unique discovery in both epoxy systems was the viscoelastic behavior at elevated temperatures.  Vitrimers are covalently ... [Click to Continue...]