Electronic Structure and Ground State Properties of PMMA Polymer: I. Step-By-Step Formation and Stereo-Regularity of the Polymeric Chain—AM1-MO Treatment

ABSTRACT

The equilibrium ground state geometric parameters of benzoyl peroxide (as free radical initiator), methylmethacrylate monomer (as a reference molecule), benzoyl-MMA radical (I), phenyl-MMA radical (II) and the three polymeric chain of PMMA (syndiotactic, isotactic, and atactic) are investigated theoretically using AMI-MO method. The stability of phenyl, benzoyl-MMA radicals, and the conformational properties of isotactic, syndiotactic, and atactic structures of PMMA polymers are discussed. The initiation and propagation steps of polymerization are investigated theoretically. The calculated geometric parameters are analyzed in terms of heat of formation, total energy, dipole moment, net charge, ionization potential, electron affinity, energy gap, and charge density maps (Total, HOMO, and LUMO).

Keywords:

• PMMA
• benzoyl peroxide
• molecular orbital calculations
• geometry optimization
• charge density

Notes

IN = initiator; R = The rest of monomer molecules; C* = active center.