US 10,802,400 B2  167  168  -continued  Comparative P AG Monomer 1  Mw ~S,900  Mw/Mn~ 1.76  Synthesis Example 2  Synthesis Example 1  Synthesis of Polymer 1  Synthesis of Polymer 2  A 2-L flask was charged with 8.4 g of 1-methylcyclopen› tyl methacrylate, 3.6 g of 4-hydroxyphenyl methacrylate, 4.5  g of 3-oxo-2,7-dioxatricyclo[4.2.l.0 4 ’ $^{8}$]nonan-9-yl meth- acrylate, 8.1 g of PAG Monomer 1, and 40 g of THF as  solvent. The reactor was cooled at - 70° C. in nitrogen  atmosphere, after which vacuum pumping and nitrogen  blow were repeated three times. The reactor was warmed up  to room temperature, whereupon 1.2 g of AIBN as polym- erization initiator was added. The reactor was heated at 60°  C., whereupon reaction ran for 15 hours. The reaction  solution was poured into 1 L of isopropyl alcohol for  precipitation. The resulting white solid was collected by  filtration and vacuum dried at 60°  C., yielding Polymer 1 as  white solid. The polymer was analyzed for composition by  $^{13}$C- and $^{1}$H-NMR and for Mw and Mw/Mn by GPC, with  the results shown below.  Polymer 1  Mw  ~  10,300  Mw/Mn~ 1.79  Polymer 2  Polymer 2 was synthesized as white solid by the same  procedure as in Synthesis Example 1 aside from using 10.3  g of PAG Monomer 2 instead of PAG Monomer 1. The  yolymer was analyzed for composition by $^{13}$C- and  H-NMR and for Mw and Mw/Mn by GPC. 