Nitrocellulose Chips (RS 1/4 Sec & RS 1/2 Sec Plasticized Resins)

Nitrocellulose (cellulose nitrate) is a semi-synthetic polymer produced through the controlled nitration of purified chemical cellulose fibres using a mixture of nitric and sulphuric acids. In industrial surface coatings and graphic arts, it is the premier film-forming resin prized for rapid solvent release, exceptional clarity, hard scratch-resistant films, and outstanding pigment wetting.

Traditional nitrocellulose is damped with 30% volatile alcohol (isopropanol or ethanol, UN 2556). In contrast, Plasticized Nitrocellulose Chips (UN 2557) are pre-phlegmatized by compounding dry nitrocellulose with 18% to 22% non-volatile plasticizer (such as acetyl tributyl citrate / ATBC or dioctyl phthalate / DOP). This eliminates solvent evaporation, prevents drying out during storage in hot tropical Kenyan warehouses, and dramatically improves handling safety.

KIKI'S Industrial Chemicals imports and stocks authentic Regular Soluble (RS) Nitrocellulose Chips in both 1/4 second and 1/2 second viscosity classifications, packaged in heavy-gauge 100kg/120kg steel cylinders and 40kg fibre drums in Nairobi, supplying commercial ink manufacturers, wood lacquer formulators, and leather finishing plants.

Demystifying 1/4 Second vs 1/2 Second Viscosity Grades

The historical designations '1/4' and '1/2' refer strictly to standard falling-ball viscosity measurements defined by ASTM D301-90. A 5/16-inch steel ball is timed as it falls through 10 inches of a standardized solution (typically 12.2% nitrocellulose by weight dissolved in a specified solvent blend at 25°C):

• RS 1/4 Second Viscosity (0.20 to 0.35 seconds): Possesses lower molecular weight chains, producing lower solution viscosity at equivalent resin concentration. This enables printing ink formulators to maximize solids content and pigment loading, delivering intense color strength and fast solvent release on flexographic and rotogravure packaging presses.
• RS 1/2 Second Viscosity (0.40 to 0.60 seconds): The universal standard for industrial wood finishes and automotive lacquers. Provides an optimal compromise between high film build and superior mechanical film toughness, scratch resistance, and cold-check resistance on timber and metal surfaces.

Dissolution Protocol and Solvent Formulation

Plasticized NC chips cannot be dissolved by dumping directly into active solvents without proper blending techniques:

• Pre-Wetting Stage: In a grounded mixing tank, chips must first be wetted with an alcohol diluent (such as isopropanol or ethanol) or aromatic hydrocarbon diluent (toluene) under low-speed agitation.
• Active Solvent Addition: Add active ester solvents (ethyl acetate, butyl acetate) or ketones under continuous stirring. The chips swell and dissolve smoothly into a clear, bright varnish without forming agglomerated 'fish-eyes' or un-wetted gel balls.

Crucial Fire Safety and Static Dissipation Protocols

Nitrocellulose is classified as a UN 2557 Class 4.1 Flammable Solid. Because nitrocellulose contains chemical nitrate ester groups (-ONO2), it carries molecularly bound oxygen within its polymer structure:

CRITICAL SAFETY WARNING: Smothering agents such as CO2, dry chemical powder, or sand CANNOT extinguish a burning mass of nitrocellulose, as the material supplies its own oxygen. Only massive, continuous flooding with deluge quantities of water will cool the material below its decomposition temperature.

Never allow nitrocellulose chips to experience friction, mechanical sparks, or static discharge. All drums, hoppers, stirrers, and operator shoes must be grounded to earth (< 10 ohms) before opening containers.