配方类型:

RUBBER, PLASTICS & WAXES

配方说明:

Monomer Emulsion Polymerization (Styrene)

配方组成:

Sodium Bicarbonate/0.05
Benzoyl Peroxide/0.05
A solution of ammonium persulfate is prepared first by dissolving
the 10 parts by weight of ammonium persulfate catalyst in 120 parts of
the ion exchange water. The emulsifier, sodium bicarbonate, and the
remainder of the water are then charged to the kettle and heated to
90'C. Ten parts by weight of ammonium persulfate solution is added to
the kettle and heated to 90'C. Ten parts by weight of ammonium
persulfate solution is added to the kettle as the monomer addition is
begun. Monomer is added slowly in a thin stream, above the surface of
the batch, at a rate of about 0.66% of charge per minute, or an addition
time of about 3 hr. At the start of every 500 parts by weight addition
of monomer, another 10 parts by weight of ammonium persulfate solution
is added, or the catalyst solution may be added continuously (dropwise)
during the addition of monomer. At the end of the monomer addition the

配制方法:

dissolve the polyvinyl alcohols in water and then add all other ingredients, using only 8-10% of the vinyl acetate as the initial charge. Heat to 75'C, then add remaining vinyl acetate monomer constantly over 1.5 to 2 hr period. Temperature should be kept at 75-80'C.
After all monomer is added, raise temperature to 90'C and hold for 0.5 hr. Cool to 35'C while agitating. Good agitation is essential.