Cardol: Cashew Nut Shell Liquid (CNSL) - Derived Starting Material for the Preparation of Partially Bio-Based Epoxy Resins

Characterization of Artificial Stone Produced with Blast Furnace Dust Waste Incorporated into a Mixture of Epoxy Resin and Cashew Nut Shell Oil

The demand for materials with improved properties and less negative impact on the environment is growing. Artificial stones are examples of these materials produced with up to 90% of particulate material joined by a binder. This article evaluates the physical and mechanical properties of two artificial stones produced with processing steel residue (blast furnace dust waste) and quartz powder. Two binders were used: pure epoxy resin, denoted as ASPB100, or a mixture of 70 wt% epoxy resin with 30 wt% cashew nut shell oil, denoted as ASPB7030. The process took place under vibration, compression (3 MPa/20 min and 90 °C) and vacuum (80 Pa). ASPB100 showed water absorption of 0.07%, while for ASPB7030, it was 0.54%. They were classified as having high mechanical strength associated with bending stress values equal to 32 and 25 MPa, respectively. Stain resistance indicated that both artificial stones had their stains removed with the tested cleaning agents. In this way, the novel artificial stones produced are sustainable alternatives for the application of blast furnace waste and cashew nut shell oil, reducing their negative impacts on the environment.

Electrochemistry Study of Bio-Based Composite Biopolymer Electrolyte-Starch/Cardol

The environmental problems generated by pollution due to polymers of petrochemical origin have led to the search for eco-friendly alternatives such as the development of biopolymers or bio-based polymers. The aim of this work was to evaluate the electrochemical behavior of a biopolymer composite made from cassava starch and cardol extracted from cashew nut shell liquid. The biopolymers were prepared using the thermochemical method, varying the synthesis pH and the cardol amounts. The biopolymers were synthesized in the form of films and characterized by cyclic voltamperometry and electrochemical impedance spectroscopy. The biopolymers showed a rich electroactivity, with three oxidation-reduction processes evidenced in the voltamperograms. On the other hand, the equivalent circuit corresponding to the impedance behavior of biopolymers integrated the processes of electron transfer resistance, electric double layer, redox reaction process, and resistance of the biopolymeric matrix. The results allowed us to conclude that the cardol content and the synthesis pH were factors that affect the electrochemical behavior of biopolymer composite films. Electrochemical processes in biopolymers were reversible and involved two-electron transfer and were diffusion-controlled processes.