Polymer Particle Size
Polymer Particle Size
(OP)
We manufacture several types of acrylic polymers using suspension polymerization. We have only one reactor so typically we will make 4-10 batches of one type then switch to the next type. With one type only we are experiencing a significant difference in particle size between the first batch in a run and subsequent batches. The polymer is a copolymer of MMA and styrene. We use BPO as the initiator and corn starch as the suspension agent. This happens every time we make this polymer type regardless of what is made before. Any ideas on why this is happening?






RE: Polymer Particle Size
Temperature.
Rate of addition of a component.
Level of agitation.
Regards
Pat
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RE: Polymer Particle Size
RE: Polymer Particle Size
Just a thought...
Dan - Owner

http://www.Hi-TecDesigns.com
RE: Polymer Particle Size
As I remember for PMMA which I expect is similar, it is an exothermic reaction and done in water with emulsifiers present. The quality of the emulsifier and the heat sink of the cold equipment is my best guess.
Regards
Pat
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RE: Polymer Particle Size
RE: Polymer Particle Size
We've tried several things. Doesn't seem to matter whether the reactor is cold or warm. We have run the 1st and 2nd batch on the same day and on a Friday/Monday. The last thing we tried was to powerwash the reactor both before and after the 1st batch thinking residuals from the previous type was causing small particle size of the 1st batch or residuals from the 1st batch was causing larger particle size of the 2nd batch. This also made no difference.
RE: Polymer Particle Size
Chris DeArmitt PhD FRSC CChem