Hidden use of bicine buffer

Details:

Dihydroxyethyl glycine, bicine for short, is a polyol glycine analogue, which is usually used as a biological buffer in biochemical detection, cosmetics or coatings. In addition, bicine can also be used to modify some new materials, such as reducing the metal aluminum ion in the polymeric material polyether ketone (PEKK).

Bicine complex metal ions

We know that bicine, as a buffer, has strong or weak complexation ability to some metal ions, which is the characteristic of its molecular structure. Bicine molecule contains two alcohol hydroxyl groups, one carboxyl group and lone electron pairs on the imino nitrogen atom. They can form coordination bonds with some metal ions and complex (chelate) specific metal ions, which can remove some metal ions from the system. Therefore, it is used to reduce aluminum ions in the refining process of crude polyether ketone.

Introduction to polyether ketone

This is a kind of polyarylether polymer composed of repeating units with two ketone bonds and one ether bond in the main chain structure. It is a special polymer material. PEKK has excellent resistance to extreme environment (Aerospace and oil exploitation), high melting point (300 ℃ - 360 ℃, softening point 168 ℃), chemical resistance and corrosion resistance; The tensile strength is 132 ~ 148mpa, which can be used as high-temperature resistant structural materials and electrical insulation materials. The hardness is comparable to metal and the weight is lighter. It is nonflammable and will not produce toxic gas; It is easy to shape above the melting point, and can also use injection molding or extrusion process to process pipe or film.

Aluminum ion in crude bicine chelated polyether ketone:

1. Mix the crude polyether ketone with the ethanol solution of diphenylsulfone, raise the temperature and reflux;

2. Add dihydroxyethyl glycine aqueous solution to the above system, continue heating and reflux, and filter after cooling to obtain the primary product of polyether ketone;

3. Put the primary product of polyether ketone and deionized water into the container for ultrasonic treatment, filter the material mixture after ultrasonic treatment with a centrifuge to remove water, and dry it to constant weight under 130 ℃ vacuum to obtain the purified polyether ketone.

After fully swelling in the ethanol solution of diphenylsulfone, bicine aqueous solution was used for chelation, and combined with high-frequency ultrasonic treatment, the metal aluminum ion in the crude product of polyetherketone was reduced to less than 30ppm, and the stability of polyetherketone at high temperature was significantly improved. Desheng is a manufacturer of biological buffer, which can provide high-quality dihydroxyethyl glycine bicine raw materials.