An Effective Expanded Graphite Coating on Polystyrene Bead for Improving Flame Retardancy.

Area of Science:

• Materials Science
• Polymer Chemistry
• Fire Safety Engineering

Background:

• Expanded polystyrene (EPS) is a common construction material in Korea but poses fire risks.
• Current flame-retardant coatings for EPS often detach during manufacturing.
• Improved flame retardancy is crucial for EPS building materials.

Purpose of the Study:

• To develop a stable flame-retardant coating for EPS beads.
• To create a two-step coating process preventing exfoliation.
• To evaluate the fire performance of the enhanced flame-retardant EPS (FR-EPS).

Main Methods:

• A novel flame-retardant coating solution using EG was applied in two steps.
• Coating process focused on uniform adhesion and preventing exfoliation.
• Fire performance tests (horizontal/vertical burning, THR, HRR) were conducted on FR-EPS.

Main Results:

• Ten FR-EPS samples met HF-1 and V-0 flammability standards.
• FR-EPS exhibited low Total Heat Release (THR) and peak Heat Release Rate (HRR).
• FR-EPS passed Korea's semi-nonflammability building material standard, unlike commercial EPS.

Conclusions:

• The two-step coating method ensures durable flame-retardant film adhesion on EPS beads.
• FR-EPS demonstrates superior flame retardancy compared to other polystyrene composites.
• This innovative FR-EPS meets critical fire safety regulations for construction.