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The synthesis and processing of polyacetylene films affects the properties. Increasing the catalyst ratio creates thicker films with a greater draw ratio, allowing them to be stretched further. [8] Lower catalyst loadings leads to the formation of dark red gels, which can be converted to films by cutting and pressing between glass plates. [20]
Superabsorbent polymer: Polymer that can absorb and retain extremely large amounts of a liquid relative to its own mass. [5] Notes: The liquid absorbed can be water or an organic liquid. The swelling ratio of a superabsorbent polymer can reach the order of 1000:1. Superabsorbent polymers for water are frequently polyelectrolytes.
Methods include emulsion polymerization, solution polymerization, suspension polymerization, and precipitation polymerization. Although the polymer dispersity and molecular weight may be improved, these methods may introduce additional processing requirements to isolate the product from a solvent.
Solution polymerization is a method of industrial polymerization. In this procedure, a monomer is dissolved in a non-reactive solvent that contains a catalyst or initiator. The reaction results in a polymer which is also soluble in the chosen solvent. Heat released by the reaction is absorbed by the solvent, reducing the reaction rate.
Specific materials and their applications include polymer-protein and polymer-drug conjugates, mediation of enzyme activity, molecular recognition processes and polymeric micelles which can deliver a drug to a specific site in the body. [19] RAFT has also been used to graft polymer chains onto polymeric surfaces, for example, polymeric ...
The final product is a dispersion of polymer particles in water. It can also be known as a polymer colloid , a latex, or commonly and inaccurately as an 'emulsion'. Smith-Ewart theory does not predict the specific polymerization behavior when the monomer is somewhat water-soluble, like methyl methacrylate or vinyl acetate .
Chain polymerization products are widely used in many aspects of life, including electronic devices, food packaging, catalyst carriers, medical materials, etc. At present, the world's highest yielding polymers such as polyethylene (PE), polyvinyl chloride (PVC), polypropylene (PP), etc. can be obtained by chain polymerization.
There are many properties of polymeric materials that influence their mechanical properties. As the degree of polymerization goes up, so does the polymer’s strength, as a longer chains have high Van der Waals interactions and chain entanglement. Long polymers can entangle, which leads to a subsequent increase in bulk modulus. [11]