Glycerol polymer crosslinked

Some polyesters have a crosslinked structure when a polyfunctional alcohol or acid is used for the synthesis. For example, phthalic anhydride and glycerol form crosslinked polymers known as alkyds (name derived from alcohol and acids). The reaction is shown schematically below ... 

A recent development has been the synthesis of bioerodible poly-phosphazenes that bear glyceryl side groups (35). The synthesis of these polymers requires a protection-deprotection sequence to reduce the functionality of the glycerol and prevent crosslinking. 

One of the first synthetic polymers to be blended with starch was poly(vinyl alcohol) (PVA). Otey et al.129,130 prepared cast films of starch and PVA from aqueous solutions containing a plasticizer (glycerol). Films were cast onto glass plates and air-dried at 130°C. Small amounts of crosslinking agent, such as formaldehyde,... 

Cross-linked pre-polymers having fractionalized molecular weights between 35,000 and 70,000 daltons with polydispersity indexes of less than 3.4 have been prepared by the free radical addition of 2-hydroxethyl methacrylate, HEMA, with 2% methacrylic acid or glycerol methacrylate. Once crosslinked, these materials are particularly useful as contact lenses because of their limited shrinkage and expansion. 

Another way of producing highly crosslinked polyesters (see Exercise 64) is to use glycerol. Alkyd resins are a polymer of this type. The polymer forms very tough coatings when baked onto a surface and is used in paints for automobiles and large appliances. Draw the structure of the polymer formed from the condensation of... 

The aim of our work is to find a new type of solid catalysts in order to be able to control the selectivity. We present in this paper some results obtained with crosslinked porous polymers. Also, we compare the behaviour of different catalysts, in particular, ion-exchange resins, in the esterification of glycerol with oleic acid. The influence of the nature of the resin as well as its swelling properties are discussed. 

The crosslinked material they obtained displayed, as one would indeed expect, very similar spectroscopic features compared with those of the starting cutin. In a subsequent study in the same vein [84], glycerol derivatives of mono- and dicarboxylic acids, whose structure simulated those present in both suberin and cutin, were prepared and characterized in an effort to simulate the biological synthesis of those natural polymers and exploit their peculiar properties, particularly their tendency to form supramolecular assemblies. 

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