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Molecular Features Behind Formation of α or β Co-Crystalline and Nanoporous-Crystalline Phases of PPO.

ABSTRACT: Guest molecular features determining the formation of α and β phases of poly(2-6-dimethyl-1,4-phenylene) oxide (PPO) are explored by collecting literature data and adding many new film preparations, both by solution casting and by guest sorption in amorphous films. Independently of the considered preparation method, the α-form is favored by the hydrophobic and bulky guest molecules, while the hydrophilic and small guest molecules favor the β-form. Furthermore, molecular modeling studies indicate that the β-form inducer guests establish stronger dispersive interactions with the PPO units than the α-form inducer guests. Thus, the achievement of co-crystalline (and derived nanoporous crystalline) α- and β-forms would result from differences in energy gain due to the host-guest interactions established at the local scale.

SUBMITTER: Golla M

PROVIDER: S-EPMC8821151 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature

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Molecular Features Behind Formation of α or β Co-Crystalline and Nanoporous-Crystalline Phases of PPO.

Golla Manohar M Cozzolino Antonietta A Nagendra Baku B Vignola Emanuele E Daniel Christophe C Rizzo Paola P Guerra Gaetano G Auriemma Finizia F D'Alterio Massimo Christian MC

Frontiers in chemistry 20220125

Guest molecular features determining the formation of α and β phases of poly(2-6-dimethyl-1,4-phenylene) oxide (PPO) are explored by collecting literature data and adding many new film preparations, both by solution casting and by guest sorption in amorphous films. Independently of the considered preparation method, the α-form is favored by the hydrophobic and bulky guest molecules, while the hydrophilic and small guest molecules favor the β-form. Furthermore, molecular modeling studies indicate ...[more]

PMID: 35145955

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