Coating classification: chelating agent

It is suggested that metal atoms or ions react with ligands containing two or more than two ligands to form a complex with ring structure, which is called chelate This kind of ligand material that can produce chelate is called chelating agent, also known as complexing agent Chinese name chelating agent Foreign name collating agent Chelating ligand brief introduction Metal atom or ion and coordination body containing two or more coordination atoms Paint agent, top 10 Chinese wall paint brands Recommended introduction: interior wall paint and exterior wall paint can achieve beautiful, clean and pleasant effects, but the effects in different environments are different, so the color of the paint will be different There are ten brands of Chinese paint, ten brands of global paint, ten brands of Chinese wall paint, and ten brands of Chinese paint, Famous trademark of Chinese paint and coating In private rooms, most of us choose according to our own personality, personal hobbies and living habits The younger generation will choose the interior wall paint with rich colors and bright colors, while the older ones will have some working experience Paint Home News: metal atoms or ions react with ligands containing two or more than two coordination atoms to form a complex with ring structure, which is called chelate This kind of ligand material that can produce chelate is called chelating agent, also known as complexing agent Chelating agent is also called chelating ligand In brief, chelating agent, metal atoms or ions interact with a ligand containing two or more than two coordination atoms to form a complex with ring structure, which is called chelate This kind of ligand material that can produce chelate is called chelating agent, also known as complexing agent Also known as chelating ligand, chelating group or mutidentate ligand There are two or more coordination atoms in the ligand, which form a chelating ring with a central atom (or ion) at the same time Because of the cyclization of chelating agent, the stability of chelates is higher than that of non chelating coordination compounds with similar composition and structure Most chelating agents are organic ligands At present, the most chelating agents have been found up to 14 teeth Oxygen and nitrogen are the most common coordination atoms, followed by sulfur, phosphorus and arsenic This kind of compound is described by "pincers" because the molecular structure is very similar to that of "crab" with two big "pincers" holding metal atoms or ions The complex ions which are formed by the combination of a positive ion (called central ion) and several neutral molecules or ions (called coordination body) are called coordination ions (also called complex ions), and the compounds containing coordination ions are called coordination compounds This coordination compound has a ring structure Its stability is higher than that of non chelates with similar composition and structure In the complex, the central ion and the ligand are bound by coordination bond Coordination bond is a special kind of covalent bond The common covalent bond is formed by two bonding atoms each producing an electron to form a common electron pair In coordination bond, one atom provides an electron pair and the other provides an empty orbit In order to distinguish, the covalent bond is represented by "one", such as H · + · H = H: H (H-H), the coordination bond is represented by "←", and the arrow points to the atom providing the empty orbit, such as Cu + NH3 = cunh3 (Cu ← NH3) If there is only one coordination atom in the ligand, only one coordination bond can be formed between the central ion and the ligand When there are more than two coordination atoms in some coordination molecules and there are two or three other non coordination atoms between the two atoms, the ligand and the central ion (or atom) can form more than two coordination bonds at the same time The number of atoms directly coordinated with the central ion is called the coordination number, usually the coordination number is 4 or 6, and there are also 2 and 8 The coordination number depends on the electronic structure and spatial factors of the central particles The most common coordination atoms are oxygen, sulfur and nitrogen Phosphorus, arsenic and selenium can also form chelates In the chelating agent molecule, the coordination atoms are connected by other atoms (mainly carbon atoms) to form a suitable structure According to the number of coordination atoms in the chelating agent molecule, it can be divided into two, three, four and six rodent chelating agents Chelating agents include inorganic and organic Most of them are organic compounds The commonly used chelating agents are polyphosphate, aminocarboxylic acid, 1,3-dione, hydroxycarboxylic acid, polyamine, etc Chelating agents have various structures, including straight chain and branched chain There are also ring chelating agents such as porphyrin derivatives and crown ether derivatives Chelating effect the chelate formed by the same metal ion and a chelating agent is more stable than the complex formed by a single rodent ligand with the same coordination atom This special stability is due to ring formation Therefore, the increase of the stability caused by the formation of chelating ring is called chelating effect The stability of chelate is measured by the stability constant of chelate The larger the stability constant is, the higher the stability of chelate is Assume that the chelate formed by chelating agent and metal ion is ml (the simplest case) Strictly speaking, the stability constant of chelate should be expressed as: the home of coatings focuses on the news and information of coatings, diatom mud, paint coatings, coating process, fire retardant coatings, and coatings, diatom mud, paint coatings, coating process, decoration knowledge and decoration effect map of fire retardant coatings,