Glass agglomeration

C.G. Wade, USP 3715247(1973) CA 78, 126471(1973) [Water-in-oil emulsion expl containing entrapped gas. An example is AN 31-7, NaN03 10, Ediylenediamine Dinitrate 10, NH4CI04 10, magnesium nitrate hexahydrate 12.3 and water 20 (heated until all dissolved), blended with a mixture of Indra 2119 wax 2 and sorbitan monooleate 10 parts, followed by addition of Corcel hollow glass agglomerates to make 100 parts]... 

Small, complex-shaped glass articles such as thread guides for the textile industry and television gun mounts for the electronics industry are made by the multiform process. The dry-milled powder is mixed with an inorganic binder and a fluid vehicle, and then atomi2ed by a spray dryer into small, dried agglomerates of glass powder and binder with good flow characteristics. They are subsequently pressed to the desired shape and fired. 

PVA Particles. Dispersions were prepared in order to examine stabilization for a core polymer having a glass transition temperature below the dispersion polymerization temperature. PVA particles prepared with a block copolymer having M PS) x 10000 showed a tendency to flocculate at ambient temperature during redispersion cycles to remove excess block copolymer, particularly if the dispersion polymerization had not proceeded to 100 conversion of monomer. It is well documented that on mixing solutions of polystyrene and poly(vinyl acetate) homopolymers phase separation tends to occur (10,11), and solubility studies (12) of PS in n-heptane suggest that PS blocks with Mn(PS) 10000 will be close to dissolution when dispersion polymerizations are performed at 3 +3 K. Consequently, we may postulate that for soft polymer particles the block copolymer is rejected from the particle because of an incompatibility effect and is adsorbed at the particle surface. If the block copolymer desorbs from the particle surface, then particle agglomeration will occur unless rapid adsorption of other copolymer molecules occurs from a reservoir of excess block copolymer. 

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