Highly selective pressure-dependent (transfer) hydrogenative depolymerization of polybutylene succinate

Area of Science:

• Catalysis
• Polymer Chemistry
• Green Chemistry

Background:

• Polybutylene succinate (PBS) is a biodegradable polyester with potential applications in sustainable materials.
• Efficient and selective depolymerization methods are needed to valorize PBS into valuable chemical monomers or intermediates.
• Current depolymerization techniques may lack selectivity or require harsh conditions.

Purpose of the Study:

• To investigate the catalytic activity of Ru-MACHO®-BH for the controlled depolymerization of polybutylene succinate (PBS).
• To explore the influence of hydrogen pressure on the selectivity of the depolymerization products.
• To demonstrate a novel transfer hydrogenation pathway for PBS deconstruction.

Main Methods:

• Catalytic depolymerization of polybutylene succinate using Ru-MACHO®-BH as the catalyst.
• Controlled application of low and elevated hydrogen pressure.
• Analysis of reaction products, including gamma-butyrolactone and 1,4-butanediol.

Main Results:

• Ru-MACHO®-BH effectively catalyzed the controlled depolymerization of polybutylene succinate.
• Under low hydrogen pressure, gamma-butyrolactone was selectively produced via a novel transfer hydrogenation mechanism involving dehydrogenation and hydrogenation.
• Increasing hydrogen pressure led to the selective generation of 1,4-butanediol.

Conclusions:

• Ru-MACHO®-BH is a highly effective catalyst for the selective depolymerization of polybutylene succinate.
• The catalyst offers tunable product selectivity (gamma-butyrolactone or 1,4-butanediol) by adjusting hydrogen pressure.
• This catalytic system presents a promising route for the sustainable valorization of polybutylene succinate.