Hydrogen bonding interactions in methacrylate monomers and polymers
Marianela T Lemon1, Melissa S Jones, Jeffrey W Stansbury
1Department of Craniofacial Biology, University of Colorado School of Dentistry, Aurora, Colorado 80045, USA.
Journal of Biomedical Materials Research. Part A
|June 15, 2007
Summary
Hydrogen bonding significantly impacts monomer and polymer properties. Bis-GMA exhibits stronger hydrogen bonding than urethane dimethacrylate (UDMA), leading to comparable mechanical strength despite lower conversion rates.
Area of Science:
- Polymer Chemistry
- Materials Science
- Organic Chemistry
Background:
- Hydrogen bonding is a critical noncovalent interaction influencing monomer and polymer characteristics.
- Bis-phenol A glycidyl methacrylate (Bis-GMA) and urethane dimethacrylate (UDMA) are key dimethacrylate monomers used in various applications.
- Understanding the role of hydrogen bonding in these monomers is essential for tailoring material properties.
Purpose of the Study:
- To investigate and compare the hydrogen bonding strength and nature in Bis-GMA and UDMA monomers and their corresponding polymers.
- To elucidate how these noncovalent interactions affect monomer viscosity, photopolymerization kinetics, and polymer mechanical properties.
- To determine the contribution of intermolecular interactions to the overall hydrogen bonding effects.
Main Methods:
- Fourier Transform Infrared (FT-IR) spectroscopy was employed to examine hydrogen bonding under various conditions (ambient, elevated temperature, dilution).
- Measurements of monomer viscosity, photopolymerization reaction kinetics, and polymer mechanical properties were conducted.
- Model compounds were used to isolate and study specific hydrogen bonding interactions.
Main Results:
- Bis-GMA demonstrated stronger hydrogen bonding compared to UDMA, with a greater contribution from intermolecular interactions.
- UDMA-based polymers achieved higher conversion levels during photopolymerization than Bis-GMA based polymers.
- Despite lower conversion, Bis-GMA polymers exhibited comparable mechanical strength due to enhanced hydrogen bonding reinforcement.
Conclusions:
- Hydrogen bonding significantly influences the polymerization reactivity and mechanical properties of dimethacrylate monomers and polymers.
- The strength and nature of hydrogen bonding, dependent on monomer structure and comonomers, can be leveraged to optimize material performance.
- Even in highly crosslinked networks, hydrogen bonding plays a crucial role in enhancing polymer properties.
Related Concept Videos
01:04Hydrogen Bonds
A hydrogen bond is formed when a weakly positive hydrogen atom already bonded to one electronegative atom (for example, the oxygen in the water molecule) is attracted to another electronegative atom from another polar molecule, such as water (H2O), hydrogen fluoride (HF), or ammonia (NH3). The huge electronegativity difference between the H atom (2.1) and the atom to which it is bonded (4.0 for an F atom, 3.5 for an O atom, or 3.0 for an N atom), combined with the very small size of an H atom...
00:26Hydrogen Bonds
Hydrogen BondsHydrogen bonds are weak attractions between atoms that have formed other chemical bonds. One of these atoms is electronegative, like oxygen, and has a partial negative charge. The other is a hydrogen atom that has bonded with another electronegative atom and has a partial positive charge.Hydrogen Bonds Control the World!Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are...
01:20Anionic Chain-Growth Polymerization: Overview
The polymerization process that involves carbanion as an intermediate is called anionic polymerization. It is also a type of addition or chain-growth polymerization. Anionic polymerization gets initiated by a strong nucleophile such as an organolithium or a Grignard reagent. The most commonly used initiator for anionic polymerization is butyl lithium. Monomers involved in anionic polymerization must possess a vinyl group bonded to one or two electron-withdrawing groups. For instance,...
02:35Noncovalent Attractions in Biomolecules
Noncovalent attractions are associations within and between molecules that influence the shape and structural stability of complexes. These interactions differ from covalent bonding in that they do not involve sharing of electrons.
Four types of noncovalent interactions are hydrogen bonds, van der Waals forces, ionic bonds, and hydrophobic interactions.
Hydrogen bonding results from the electrostatic attraction of a hydrogen atom covalently bonded to a strong-electronegative atom like oxygen,...
Four types of noncovalent interactions are hydrogen bonds, van der Waals forces, ionic bonds, and hydrophobic interactions.
Hydrogen bonding results from the electrostatic attraction of a hydrogen atom covalently bonded to a strong-electronegative atom like oxygen,...
02:35Noncovalent Attractions in Biomolecules
Noncovalent attractions are associations within and between molecules that influence the shape and structural stability of complexes. These interactions differ from covalent bonding in that they do not involve sharing of electrons.
Four types of noncovalent interactions are hydrogen bonds, van der Waals forces, ionic bonds, and hydrophobic interactions.
Hydrogen bonding results from the electrostatic attraction of a hydrogen atom covalently bonded to a strong-electronegative atom like oxygen,...
Four types of noncovalent interactions are hydrogen bonds, van der Waals forces, ionic bonds, and hydrophobic interactions.
Hydrogen bonding results from the electrostatic attraction of a hydrogen atom covalently bonded to a strong-electronegative atom like oxygen,...
01:17Radical Chain-Growth Polymerization: Chain Branching
The skeletal structure of polymers synthesized via radical polymerization is always branched. For example, the polymerization of ethylene by radical polymerization results in a low-density grade of polyethylene with a heavily branched skeletal structure. Here, the radical site abstracts hydrogen from the growing chain, and the radical site shifts from the end (a primary carbon center) to anywhere within the growing chain (a secondary carbon center). Consequently, the part of the chain from the...