an instance of OCL.Molecule
Optionalalpha?: Moleculealpha end group, default is an hydrogen
Optionalcount?: numbernumber of units
Optionalgamma?: Moleculeomega end group, default is an hydrogen
OptionalmarkMonomer?: booleanmark the different units of the polymer in the atom map
Create a polymer from a unit, alpha and omega groups A unit must contain a R1 and a R2 An alpha end group must contain a R1 An omega end group must contain a R2