Broadly, the monomer is soluble in the liquid but the polymer is insoluble. It is thermodynamically unfavorable for the polymer to expose the monomer units to the surrounding liquid. Instead, the polymer will change its configuration to minimize that interaction.

For a more accurate description, search Flory-Huggins theory, e.g., https://web.stanford.edu/class/cheme160/lectures/lecture9.pdf

Dear all, years ago I answered a question with a similar context. Suspension is a heterophase system, composed of immiscible phases (deslike each other), once put under the agitation shear, the dispersed phase will take a sphere (or -like) form because it is the shape that has the minimum possible surface area per volume, so that the contact interphase (or interface) between unlike phases will be at its lowest possible. It is also possible to use surface free energy in explaning this. To simplify this with an example, lets take a cube with a 1 liter volume and a sphere (balloon) with a volume of 1 liter also. If the surface areas are deduced, the one of the cube (or any other geometrical form) is higher than that of the sphere (at equal volumes condition of course).

Now, the size of suspension particles depends essentially on shear level, concentration, and to lower extent on the type and concentration of the suspention stabilizer. My Regards

Dear Kavitha Karanam ! Suspension polymerization is similar to a reaction in bulk, when a polymer in a test tube suddenly turns into a solid resin. The monomer turns into a polymer. The test tube in this case is water. And the monomer in the water is in the form of droplets, which solidify. So that the drops do not stick together, I make a gel out of water and the drops freeze in perfectly round beautiful spheres. See the articleArticle Suspension copolymerization of divinylbenzene in a gel medium