PLA Biodegradable Foam Bead Production Line
PLA (Polylactic Acid) is a fully biodegradable eco-friendly material included in national industrial incentive catalogs. It is manufactured from starch extracted from renewable plant sources via microbial fermentation to produce lactic acid, followed by lactide synthesis and polymerization into PLA resin. Featuring eco-friendliness, complete biodegradability and food-grade safety, PLA outperforms paper packaging in comprehensive functional performance and meets global sustainable manufacturing standards.
PLA foam beads can thermoform customized foam parts to replace disposable EPS, EPE and EPP packaging materials. The complete PLA foam bead production line supports flexible formulation adjustment with various functional additives to satisfy customized requirements for lunch boxes and buffer pads. Most mainstream equipment suppliers only develop basic sheet machines, while Foshan Gaoming Keli Machinery Co., Ltd. specializes in biodegradable foam equipment R&D and delivers integrated turnkey solutions for both PLA beads and sheets.
Pure PLA suffers weak thermal stability and high brittleness, leading to poor impact resistance after direct foaming. Copolymer foaming serves as the universal industrial optimization method, which retains full biodegradability while greatly boosting product toughness and drop resistance. This modified foaming process perfectly matches the two-stage supercritical CO₂ extruder independently developed by Keli Machinery【Internal Link: Supercritical CO₂ Extrusion Foaming Technology: Process, Equipment & New Energy Applications】, delivering consistent modification performance during stable operation of the whole supercritical foaming production line.
As a polyester material, PLA must be dried prior to extrusion foaming. Dried PLA pellets and additives are separately fed into the primary extruder via loss-in-weight feeders. After full plasticization and stable backpressure buildup inside the barrel, CO₂ is injected and dissolved into the melt under supercritical state. The mixed melt transfers to the secondary extruder for precise temperature regulation, then foams rapidly under extreme pressure difference at the die before being cut into uniform beads by a pelletizer. The whole PLA foam bead production line realizes full automatic temperature and pressure control without repeated manual adjustment.
Low crystallinity and poor heat resistance are core process bottlenecks during PLA foaming, which can be solved by chain extension, branching and crosslinking treatments. High-pressure CO₂ exerts plasticizing effects to accelerate PLA crystallization rate. Modified PLA processed by the complete supercritical CO₂ foaming production line achieves a maximum foaming ratio of 25–30 times, reducing product weight by 20–60% compared with ordinary PLA thermoformed sheets. It withstands temperatures up to 130℃ and maintains excellent compression resistance at -20℃, suitable for microwave heating and fresh cold storage. Compared with pulp products, modified PLA foam boasts superior waterproof, oil-proof and thermal insulation properties without heavy metal residues.
Bead foaming technology gains wide recognition for producing high-magnification, complex-shaped foam parts. Molded beads bond together to form finished products with precise dimensional accuracy, delivering equivalent energy absorption, heat insulation and sound insulation performance as continuous extruded sheets. Modified PLA foam tableware has achieved mass production, with expanding application scope covering food packaging, textiles, sanitary supplies, agriculture, environmental protection, 3D printing, medical devices, auto parts, fruit trays, salad containers, egg cartons, cup lids, lunch boxes and e-commerce cushion liners.