Understanding the influence of hydrogen bonding and diisocyanate symmetry on the morphology and properties of segmented polyurethanes and polyureas: Computational and experimental study

Date

2014-09-02

Author

Sami, Selim
Yıldırım, Erol
Yurtsever, Mine
Yurtsever, Ersin
Yilgor, Emel
Yilgor, Iskender
Wilkes, Garth L.

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

420
views

0
downloads

Quantum mechanical calculations (QMC) and dissipative particle dynamics (DPD) siniulations were utilized to understand the nature of the short and long-range hydrogen bonding and its influence on the microphase morphology in segmented polyurethanes and segmented polyureas prepared without chain extenders through the stoichiometric reactions of hydroxy or amine terminated poly(tetramethylene oxide) (PTMO-1000) with 1,4-phenylene diisocyanate (PPDI) and 1,3-phenylene diisocyanate (MPDI). The possibility of long-range connectivity due to a network of well-ordered hydrogen bonds between symmetrical PPDI and kinked MPDI based model urethane and urea compounds were also investigated. Special emphasis was given on the understanding of the influence of diisocyanate symmetry and nature of the hydrogen bonding between hard segments on the morphology development. QMC results obtained clearly indicated the possibility of long-range ordering of hydrogen bonds between PPDI based urethane and urea groups, while MPDI based systems did not display such a behavior. DPD results strongly supported the QMC studies and clearly demonstrated the possibility of long-range connectivity of hydrogen bonds between urethane and urea groups in PPDI based segmented copolymers, leading to the formation of microphase separated morphologies in these systems, which was not observed in the kinked MPDI based segmented urethane and urea copolymers. Computational results obtained strongly supported the experimental observations reported on the morphology and thermal and mechanical properties of these segmented polyurethanes and polyureas based on PPDI and MPDI.

Subject Keywords

Organic Chemistry, Polymers and Plastics

URI

https://hdl.handle.net/11511/34350

Journal

POLYMER

DOI

https://doi.org/10.1016/j.polymer.2014.07.028

Collections

Department of Chemistry, Article

Suggestions

OpenMETU
Core

A new soluble conducting polymer and its electrochromic devices YİLDİZ, UMİT HAKAN; SAHİN, ELİF; Akhmedov, IM; Tanyeli, Cihangir; Toppare, Levent Kamil (Wiley, 2006-04-01) A new polythiophene derivative was synthesized by both chemical and electrochemical oxidative polymerization of 1-(1-phenylethyl)-2,5-di(2-thienyl)-1H-pyrrole (PETPy). Of which the chemical method produces a polymer that is completely soluble in organic solvents. The structures of both the monomer and the soluble polymer were elucidated by nuclear magnetic resonance (H-1 and C-13 NMR) and Fourier transform infrared (FTIR) spectroscopy. The average molecular weight has been determined by gel permeation chrom...
DIPOLE-MOMENTS OF COPOLYMERS IN RELATION TO THE DISTRIBUTION OF POLAR MONOMER UNIT SEQUENCES KUCUKYAVUZ, Z; BAYSAL, BM (Elsevier BV, 1991-01-01) A method for evaluating the dipole moments of copolymers in relation to the distribution of polar unit sequences is proposed. Experimental data on the synthesis and dipole moments of styrene-p-chlorostyrene and styrene-p-methoxystyrene copolymers were used to calculate the effective dipole moment of a polar unit in a copolymer. For this purpose, we assumed the following effective moment values for the corresponding polar unit sequences along the copolymer chains: when both of the nearest neighbours are pola...
On the cryptoannulenic behavior of certain corannulenes Türker, Burhan Lemi (Informa UK Limited, 1996-01-01) Cryptoannulenic behavior of certain corannulenes is investigated within the Framework of Huckel molecular orbital theory. It has been found that the cryptoannulenic behavior of the corannulenes studied, generally arises from the type of their individual peripheral rings (4m or 4m + 2) but not from the type of the inner or outer periphery of the whole corannulene system.
Fabrication of a Novel Polymeric Scaffold for Amperometric Laccase Biosensor Soylemez, Saniye; Bekmezci, Aybüke; Göker, Seza; Toppare, Levent Kamil (Wiley, 2019-11-14) Present work displays the preparation of an electrochemical biosensor using a conjugated polymer and laccase enzyme for catechol quantification in samples. The biosensing system is based on an enzyme immobilization on polymer modified graphite transducer surface. For that purpose, a random conjugated polymer, thienothiophene-benzoxadiazole-alt-benzodithiophene (BOTT), was coated onto a graphite electrode surface via drop casting method followed by immobilization of a biomolecule (laccase) for sensing experi...
Electrochemical polymerisation of 2-aminofluorene in ethylalcohol/water medium Imamoglu, T; Önal, Ahmet Muhtar (Elsevier BV, 2004-08-01) Electrochemical polymerisation of 2-aminofluorene, 2AF, was investigated in ethylalcohol/water mixture (3:2, v:v) in the presence of HClO4 as the supporting electrolyte via constant potential electrolysis, CPE. Prior to CPE, electrochemical behaviour of the monomer was investigated in the same solvent electrolyte couple utilising cyclic voltammetry, CV. Electrochemical polymerisation of the monomer yielded insoluble, dark bluish-green, conducting polymer deposit on the electrode surface. Characterisation of...

Citation Formats

S. Sami et al., “Understanding the influence of hydrogen bonding and diisocyanate symmetry on the morphology and properties of segmented polyurethanes and polyureas: Computational and experimental study,” POLYMER, pp. 4563–4576, 2014, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/34350.