Resin kits can be bought from various sources, including craft stores, online marketplaces like Amazon or Etsy, and specialized resin supplier websites. Craft stores often offer a selection of basic kits, making them a good starting point for beginners. For a wider variety of options, including different types of resins (e.g., epoxy, UV resin) and specialty colorants or molds, online marketplaces and dedicated resin suppliers' websites are ideal. Suppliers such as ArtResin, Alumilite, and Smooth-On provide high-quality resins suitable for different projects, along with detailed product information and usage instructions. Additionally, buying directly from these specialized suppliers can offer access to expert advice and customer support for your resin projects.

Polymers swell in water due to the process called osmosis, where water molecules move from a region of high concentration (the water) to a region of lower concentration (the polymer). This movement is facilitated by the polymer's molecular structure, which contains hydrophilic (water-loving) segments. When these hydrophilic parts interact with water, they attract and hold onto water molecules. Additionally, as water molecules infiltrate the polymer, they force the polymer chains apart, causing the material to expand or swell. The degree of swelling depends on the nature of the polymer, including its crosslink density. Highly crosslinked polymers swell less because the tight network restricts expansion, while loosely crosslinked polymers can absorb a significant amount of water, leading to substantial swelling. This behavior is crucial in various applications, such as in hydrogels in biomedical devices, where the swelling property is leveraged for drug delivery systems, wound dressings, and tissue engineering scaffolds.

Amino acids are joined together through a process called dehydration synthesis, forming a covalent bond known as a peptide bond. This reaction occurs between the amino group of one amino acid and the carboxyl group of another, releasing a molecule of water as a byproduct. The resulting chain of amino acids is called a polypeptide. As more amino acids are added, this chain folds into a specific three-dimensional structure, depending on the sequence and properties of the amino acids it contains, ultimately forming a functional protein. The process is catalyzed by enzymes and is crucial for the synthesis of proteins, which play vital roles in virtually all biological processes, including catalysis, transport, structure, and regulation within organisms.