Related Experiment Video
Updated: Jun 16, 2026
09:22
Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
Surface morphological changes in monolayers of aromatic polyamides containing various N-alkyl side chains
Atsuhiro Fujimori1, Satoshi Chiba, Natsuki Sato
1Graduate School of Science and Engineering, Yamagata University, Jonan 4-3-16, Yonezawa, Yamagata, 992-8510, Japan. fujimori@yz.yzmzgata-u.ac.jp
The Journal of Physical Chemistry. B
|January 22, 2010
Summary
Researchers synthesized aromatic polyamides (PABA(n)) with varying side chain lengths to study their solid-state structures. The synthesis method allows control over crystal structure, molecular arrangement, and surface morphology of polymer monolayers.
Area of Science:
- Polymer Science
- Materials Science
- Surface Chemistry
Background:
- Aromatic polyamides (PABA(n)) with rigid main chains and flexible side chains were synthesized.
- Understanding their solid-state structures is crucial for material applications.
Purpose of the Study:
- To investigate the molecular orientation and surface morphology of PABA(n) polymer monolayers.
- To establish a correlation between side chain length and the resulting solid-state structure.
Main Methods:
- Surface pressure-area (pi-A) isotherm measurements.
- In-plane and out-of-plane X-ray diffraction (XRD).
- Polarized infrared spectroscopy and atomic force microscopy (AFM).
Main Results:
- PABA(1) exhibited monoclinic packing, PABA(3-5) showed orthorhombic packing, and PABA(7-8) formed amorphous polymers.
- PABA(17) formed a 2D hexagonal lattice and a highly ordered layer structure with side chain crystals.
- All synthesized polymer monolayers condensed highly on water surfaces, with varying degrees of order based on side chain length.
Conclusions:
- The synthesis method effectively controls the crystal structure (third-order structure), molecular arrangement, and surface morphology of PABA(n) monolayers.
- Side chain length is a critical factor determining the packing pattern and morphology, ranging from crystalline to amorphous.
- The study demonstrates precise control over polymer self-assembly at the molecular level.
Related Concept Videos
01:14Polymer Classification: Architecture
Polymers are classified as linear or branched on the basis of their chain architecture. The polymer chains in linear polymers have a long chain-like structure with minimal to no branching at all. Even if a polymer features large substituent groups on the monomer, which appear as branches to the skeleton, it is not considered a branched polymer. A branched polymer contains secondary polymer chains that arise from the main polymer chain. The branching occurs when the polymer growth shifts from...
01:24Characteristics and Nomenclature of Copolymers
Copolymers are the products obtained from the polymerization of multiple monomer species. So, in a polymer chain itself, there can be multiple repeating units that come from different monomers. The process of synthesizing a polymer from different monomer species is called copolymerization. When two monomers are involved, the polymer is known as a bipolymer. Polymers with three and four monomers are termed terpolymers and quaterpolymers, respectively. Figure 1 depicts the copolymerization of...
01:21Polymer Classification: Crystallinity
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
01:26Polymer Classification: Stereospecificity
Polymerization generates chiral centers along the entire backbone of a polymer chain. Accordingly, the stereochemistry of the substituent group has a significant effect on polymer properties. Polymers formed from monosubstituted alkene monomers feature chiral carbons at every alternate position in the polymer backbone. Relative to the predominant orientation of substituents at the adjacent chiral carbons, the polymer can exist in three different configurations: isotactic, syndiotactic, and...
01:03Step-Growth Polymerization: Overview
Step-growth or condensation polymerization is a stepwise reaction of bi or multifunctional monomers to form long-chain polymers. As all the monomers are reactive, most of the monomers are consumed at the early stages of the reaction to form small chains of reactive oligomers, which then combine to form long polymer chains in the late stages. Hence, the reaction has to proceed for a long time to achieve high molecular weight polymers.
Many natural and synthetic polymers are produced by...
Many natural and synthetic polymers are produced by...
01:23Nomenclature of Aromatic Compounds with a Single Substituent
Benzene is the simplest aromatic hydrocarbon or arene. The IUPAC names for simple monosubstituted benzene derivatives are derived by adding the substituent's name as a prefix to the parent benzene. For example, halobenzene, where the halogen could be fluoro (F), chloro (Cl), bromo (Br), and iodo (I).