Пиридинтрифенилборан

Description

Pyridine triphenylborane (PTPB) is a 1:1 complex of triphenylborane with pyridine, an organoelement compound of boron. The boron atom in the complex has a tetrahedral environment (T-4): three phenyl residues and a coordination bond with the pyridine nitrogen atom. Industrial use: biocide of antifouling paints for ship hulls. The compound is an organotin substitute: after the ban on tributyltin, PTPB became part of copper-free self-polishing antifouling paints widely used in Japan, and is used both independently and in conjunction with copper(I) oxide.

Basic Attributes

• CAS No.: 971-66-4
• Chemical formula: C23H20BN
• Molecular weight: 321.223
• Exact weight: 321.168884
• DSSTox ID: DTXSID20448581
• HS code: 2933399090
• PSA Specifications: 8.39000
• XLogP3: 3.28440
• English name: Pyridine-triphenylborane
• Synonyms: pyridine complex with triphenylborane; boron, triphenyl(pyridine)-, (T-4)-; triphenyl(pyridin-1-ium-1-yl)borate

Physico-chemical characteristics

• Melting point: 214–215 °C (with decomposition)
• Boiling point: 348 °C at 760 mm Hg. Art.

The small polar surface area (PSA 8.39) and XLogP3 3.28 indicate the lipophilic nature of the molecule - it is retained in the polymer coating matrix and gradually releases into the water as the film is polished.

Scope of application

• biocide for antifouling marine paints, including copper-free self-polishing compounds
• combined use with copper(I) oxide as an additive to marine coatings
• replacement of organotin antifouling compounds phased out for environmental reasons

Control and regulation

The rate of leaching of PTPB from antifouling paint is standardized by the international standard ISO 15181-4:2008 “Paints and varnishes. Determination of the rate of release of biocides from antifouling paints. Part 4: determination of the concentration of pyridine triphenylborane (PTPB) in the extract and calculation of the release rate.” The standard specifies the equipment and methodology for determining the amount of substance transferred from the coating to artificial seawater. For analytical control, HPLC methods with UV detection have been developed to determine PTPB in seawater at the ppb level, as well as capillary zone electrophoresis with field enhancement upon sample injection for the simultaneous determination of PTPB and its decomposition products in paint and varnish production waste.

Ecology

The compound decomposes in seawater. The acute toxicity of major decomposition products to marine organisms has been studied separately; The most toxic of them was diphenylborane hydroxide (DPB). This is taken into account when assessing the environmental load from antifouling coatings.

Storage and handling

GHS classification, transport codes and toxicological data are not provided in the original card. The product decomposes already upon melting (214–215 °C), so heating above this limit is unacceptable. Storage - in a tightly closed container, in a cool, dry place, away from heat sources and oxidizing agents. Do not dispose of washouts and residues into water bodies: the substance is intended to suppress marine fouling and acts on aquatic organisms.