Related Experiment Video
Updated: Apr 19, 2026
09:22
Self-assembling Morphologies Obtained from Helical Polycarbodiimide Copolymers and Their Triazole Derivatives
Published on: February 7, 2017
8.4K
Structural characterization of telechelic polyisobutylene diol
Sanjib Banerjee1, Priyank N Shah1, Youncheol Jeong2
1Polymer Science Program, Department of Chemistry, University of Massachusetts Lowell, One University Avenue, Lowell, Massachusetts 01854, USA.
Journal of Chromatography. A
|December 24, 2014
Summary
This study assessed the purity of telechelic polyisobutylene diol (PIB-diol) using advanced chromatography and mass spectrometry. Results show high chemical homogeneity (95.3% PIB-diol), indicating suitability for synthesizing high molecular weight polyurethanes.
Area of Science:
- Polymer Chemistry
- Analytical Chemistry
- Materials Science
Background:
- Telechelic polyisobutylene diol (PIB-diol) is a crucial monomer for synthesizing high-performance polymers like polyurethanes.
- Ensuring the chemical homogeneity of PIB-diol is essential for controlling polymer properties and achieving desired molecular weights.
- Previous methods for PIB-diol characterization may not fully resolve its chemical heterogeneity.
Purpose of the Study:
- To investigate the chemical homogeneity of telechelic polyisobutylene diol (PIB-diol) synthesized via a specific route.
- To develop and apply analytical techniques for accurate separation and quantification of different PIB species.
- To determine the suitability of the synthesized PIB-diol for high molecular weight polyurethane production.
Main Methods:
- Synthesis of allyl telechelic polyisobutylene (PIB) followed by hydroboration-oxidation to yield PIB-diol.
- Development of a normal phase gradient High-Performance Liquid Chromatography (HPLC) method for separating PIB species.
- Utilizing Liquid Chromatography at Critical Conditions (LCCC) with a Refractive Index (RI) detector for chemical heterogeneity analysis.
- Employing Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) for component identification.
Main Results:
- The developed HPLC method successfully separated the synthesized PIB-diol into three distinct components: PIB-diol, PIB-monool, and non-functional PIB.
- MALDI-TOF MS analysis indicated incomplete reaction during the synthesis of allyl telechelic PIB.
- LCCC analysis quantified the chemical composition: 95.3% PIB-diol, 3.3% PIB-monool, and 1.4% non-functional PIB.
- The calculated number average functionality (Fn) was determined to be 1.94.
Conclusions:
- The synthesized telechelic PIB-diol exhibits high chemical homogeneity, with over 95% purity.
- The analytical methodologies employed (HPLC, LCCC, MALDI-TOF MS) are effective for characterizing PIB-diol heterogeneity.
- The high quality and functionality of the PIB-diol make it suitable for the synthesis of high molecular weight polyurethanes.
Related Concept Videos
01:16Structure of Conjugated Dienes
8.5K
Introduction
Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the...
Conjugated dienes are compounds characterized by the presence of alternating double and single bonds. In a conjugated system like 1,3-butadiene, the unhybridized 2p orbital on each carbon overlaps continuously, allowing the π electrons to be delocalized across the entire molecule. In contrast, this type of overlap does not occur in cumulated and isolated dienes, such as 2,3-pentadiene and 1,4-pentadiene, respectively. Instead, the π electrons remain localized between the...
8.5K
01:26Polymer Classification: Stereospecificity
3.5K
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...
3.5K
01:14Polymer Classification: Architecture
4.2K
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...
4.2K
01:28Stability of Conjugated Dienes
4.8K
Introduction
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
A comparison of the enthalpies of hydrogenation of dienes reveals that conjugated dienes release less heat on hydrogenation, rendering them more stable than their nonconjugated analogs.
4.8K
01:29Diels–Alder Reaction: Characteristics of Dienes
5.8K
The Diels–Alder reaction brings together a diene and a dienophile to form a six-membered ring. Both components have unique characteristics that influence the rate of the reaction.
Characteristics of the diene
Conformation
The simplest example of a diene is 1,3-butadiene, an acyclic conjugated π system. At room temperature, the molecule exists as a mixture of s-cis and s-trans conformers by virtue of rotation around the carbon–carbon single bond. Although the s-trans isomer is...
Characteristics of the diene
Conformation
The simplest example of a diene is 1,3-butadiene, an acyclic conjugated π system. At room temperature, the molecule exists as a mixture of s-cis and s-trans conformers by virtue of rotation around the carbon–carbon single bond. Although the s-trans isomer is...
5.8K
01:24π Molecular Orbitals of 1,3-Butadiene
12.9K
Conjugated dienes have lower heats of hydrogenation than cumulated and isolated dienes, making them more stable. The enhanced stabilization of conjugated systems can be understood from their π molecular orbitals.
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the...
The simplest conjugated diene is 1,3-butadiene: a four-carbon system where each carbon is sp2-hybridized and has an unhybridized p orbital that contains an unpaired electron. According to molecular orbital theory, atomic orbitals combine to form molecular orbitals such that the...
12.9K