Acrylic acid spray drying

Acrylic Acid 118 2.4 Water spray, dry chemical, alcohol foam or carbon dioxide Not pertinent May polymerize and explode 374 No ... 

CsHjoOj Combustible liquid. Forms explosive mixture with air [explosion limits in air (vol %) 1.6 to uel unknown flash point 149°F/65°C Fire Rating 1]. Unless inhibited (200 ppm hydroquinone recommended), polymerization may occur avoid exposure to high temperatures, ultraviolet light, free-radical initiators. Reacts with water with release of heat may not be violent if not contained. Strong oxidizers may cause fne and explosions. Reacts violently with sodium peroxide, uranium fluoride. Incompatible with strong acids, nitrates. Incompatible with sulfuric acid, nitric acid, caustics, aliphatic amines, isocyanates, boranes. Thermal decomposition releases toxic acrid fumes of acrolein and acrylic acid. On small fires, use dry chemical powder (such as Purple-K-Powder), water spray, alcohol-resistant foam, or CO2 extinguishers. 

EXPLOSION and FIRE CONCERNS combustible NFPA rating Health 3, Flammability 2, Reactivity 0 flammable liquid when exposed to heat, flame or oxidizers reacts violently with acetic acid, acetic anhydride, acrylic acid, acrylonitrile, allyl chloride, carbon disulfide, chlorosulfonic acid, hydrochloric acid, nitric acid, sulfuric acid, ethylene chlorohydrin, oleum, acrolein, or vinyl acetate heating to decomposition emits carbon monoxide, carbon dioxide, hydrocarbons, toxic oxides of nitrogen, and toxic amine vapors use water spray, dry chemical, alcohol foam, or carbon dioxide for firefighting purposes. 

Combustible liquid flash point (closed cup) 54°C (130°F), (open cup) 68 C (155°F) vapor pressure 31 torr at 25°C (77°F) vapor density 2.5 (air = 1) autoignition tempera-tnre 360°C (680°F). Vapors of acrylic acid form explosive mixtures with air within the range 2.9-8.0% by volume in air. Fire-extingnishing agent water spray, alcohol foam, dry chemical, or CO2 nse a water spray to flnsh and dilute the spill and to disperse the vapors. 

Coucke, D. Schotsaert, M. Libert, C. Pringels, E. Vervaet, C. Foreman, R Saelens, X. Remon, J.R Spray-dried powders of starch and crosslinked poly(acrylic acid) as carriers for nasal delivery of inactivated influenza vaccine. Vaccine 2009, 27 (8), 1279-1286. 

One specific polymer type that has been employed in the spray drying of microspheres to modify release is acrylic resin. A commercial blend of neutral methacrylic acid esters was used for the preparation of spray-dried controlled release microcapsules containing model drugs (34). Dissolution results of tablets compressed from the... 

Aqueous solutions of salts of acrylic acid that may contain between 0.5% and 3.0% of a water-soluble initiator have been sprayed into a chamber in which the air is heated between 150° and 485°C. The polymer forms rapidly by this spray-drying-polymerization process [105]. Solutions of mixtures of salts of acrylic acid have also been dripped onto oppositely rotating, steam-heated rolls. The dried powder could be scraped from the rolls before the end of a revolution of the roll. In this procedure, 0.5% on the monomer of a persulfate salt was added to the monomer solution. The rolls were 1 ft in diameter, 4 mils apart, rotating at 5.5 rpm. Table IX gives some observations made on this method of polymerization [106]. 

Fig. 20.2 Flow diagram of process development how to polymerize in a spray (left) with regard to competition of drying the drops (right), diagram shows decreasing drop diameter of initial 10, 100 and 1000 pm drops plus 100 pm drop with mixture of acrylic acid and 50% water at a temperature of 70 °C...

Fig. 20.21 Competition of polymerization and drying—different studies of a single droplet being injected in a spray dryer. Showing the drop sizes and mean drop temperatures or mass fraction of acrylic acid over time if drops with a diameter of 10 pm (at top left and right), 100 pm (at bottom left) and 1000 pm (at bottom right) are calculated by the use of (20.35)-(20.38)...

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