Raw Material to Produce Footwear Hot Melt Sheet

In footwear manufacturing, hot melt sheets are crucial shaping materials for areas like the toe and heel, with their performance directly influencing the shoe’s support, durability, and comfort. The four commonly used raw materials to produce Footwear Hot Melt Sheet include PETG chips, low-melting point polyester (LMPET), TPU (Thermoplastic Polyurethane), and EVA (Ethylene-Vinyl Acetate). These four materials have unique properties, making them suitable for different shoes and functional requirements. The following is a detailed discussion of material characteristics, application scenarios, a comparative analysis, and industry trends.

1 PETG Chip

1.1 Material Properties

High Transparency and Gloss: PETG resin is an amorphous copolyester with transparency similar to acrylic, making it suitable for aesthetically appealing shoes (such as sandals or fashion footwear).
Excellent Toughness: PETG resin has superior impact resistance and bending strength compared to standard PET, making it less prone to cracking and ideal for complex designs.
Moderate Processing Temperature: With a melting point of around 80- 120℃, PETG has better flowability than LMPET, making it suitable for injection molding or hot-press forming.
Chemical Resistance: PETG resin is highly resistant to solvents such as oils and alcohol, making it suitable for specialized footwear (e.g., medical protective shoes).

1.2 Application Scenarios

Transparent hot melt adhesive film: used in sandals or high heels as invisible support pieces that combine both aesthetics and functionality
Complex Structure Support: made into uniquely shaped hot melt slices (e.g., hollow designs) using injection molding, which enhances design flexibility
Chemical-Resistant Footwear: used in shoes for medical or laboratory environments where resistance to disinfectants is required.

1.3 Advantages and Limitations

Advantages: Exceptional transparency, toughness, and chemical resistance, with high design flexibility.
Limitations: Higher cost than EVA and LMPET and lower support hardness than TPU, requiring reinforcement for support.

We can supply PETG Resin. For more details, please click https://www.polyestermfg.com/petg-chip/.

2 Low-Melting Point Polyester (LMPET) Chip

2.1 Material Properties

Low-Temperature Bonding: with a melting point of 90-180℃, LMPET saves energy and avoids heat damage to substrates
Lightweight: Low density (1.2-1.4 g/cm³) helps reduce the overall weight of the shoes.
Eco-Friendly: solvent-free and recyclable

2.2 Application Scenarios

Formal Shoe Shaping: used for low-temperature hot-press bonding with leather to maintain the stiffness of the toe area
Composite Reinforcement Layers: combined with non-woven fabrics to improve bending resistance (e.g., used in business shoe hot-melt sheet)
Environmentally Friendly Process: replacing solvent-based adhesives to simplify production processes

2.3 Advantages and Limitations

Advantages: Energy-efficient at low temperatures, lightweight, and eco-friendly.
Limitations: Poor flexibility, requiring modification with elastomers.

For more information about low-melt polyester chips, you can refer to https://www.polyestermfg.com/low-melting-polyester-chip/.

3 TPU (Thermoplastic Polyurethane)

3.1 Material Properties

High Elasticity and Wear Resistance: Offering a wide hardness range (60A-90A), providing strong dynamic support
Weather Resistance: Resistant to UV radiation and hydrolysis, making it suitable for outdoor shoes
Higher Processing Temperature: requiring a processing temperature of 120-180C and specialized equipment.

3.2 Application Scenarios

Sports Shoe Anti-Twist Pieces: Used in basketball and hiking shoes to provide arch support.
Transparent Elastic Support: Transparent TPU hot melt sheet for stylish sports shoes.
Functional Composites: Combining with carbon fiber to enhance the performance of high-end footwear

3.3 Advantages and Limitations

Advantages: Unmatched elasticity, wear resistance, and aging resistance
Limitations: Higher cost and significant energy consumption during processing

4 EVA (Ethylene-Vinyl Acetate)

4.1 Material Properties

Lightweight and Shock-Absorbent: EVA has a low density (0.93-0.95g/cm³) and excellent shock-absorbing properties when foamed.
Low-Temperature Processability: With a melting point of 70-100℃, EVA is suitable for low-cost, high-volume production.

4.2 Application Scenarios

Sports Shoe Insoles: foam EVA used for running shoes
Children’s Shoe Support: soft, anti-chafing material that improves comfort
Economic Solutions: lightweight support for casual shoes

4.3 Advantages and Limitations

Advantages: low cost, lightweight, and easy to process
Limitations: weak support, prone to deformation with long-term use

5 Comparative Analysis Of Four Types of Materials

PROPERTIES	PETG	LMPET	TPU	EVA
Transparency	High transparency	Translucent/opaque	transparent	non-transparent
Hardness and Support	Medium hardness, good toughness	High hardness, rigid support	High elasticity, dynamic support	Low hardness, slow shock
Working Temperature	80~120℃	80~120℃	120~180℃	70~100℃
Cost	higher	intermediate	high	low
Environmental Protection Properties	Recyclable, requiring a special process	Recyclable, solvent-free	Recyclable, but high energy consumption	Recyclable, complex foaming process
Typical Application	Fashion shoes, medical shoes	Dress shoes, business shoes	Sports shoes, outdoor shoes	Casual shoes, children’s shoes

6 Composite Applications and Industry Trends

6.1 Material Composite Innovations

PETG + TPU: A transparent PETG outer layer combined with an elastic TPU inner layer, used for stylish support in sports sandals
LMPET + Carbon Fiber: A low-temperature bonding layer (LMPET) combined with high-strength carbon fiber, enhancing lightweight torsional performance
EVA + PETG Foaming: An EVA foam base covered with a PETG film on the surface to improve wear resistance and aesthetics

6.2 Future Development Directions

Sustainable Materials: Bio-based PETG and biodegradable TPU to reduce environmental impact
Smart Responsive Materials: Temperature-sensitive TPU or light-sensitive PETG that enable hot melt slices to provide adaptive support (e.g., hardening during running)
3D Printing Customization: Using the melting properties of PETG and TPU to 3D print personalized hot melt sheet structures

6.3 Material Selection Recommendations

High-End Sports Shoes: TPU (main support) + PETG (transparent decoration)
Formal Shoes/Business Shoes: LMPET (shaping layer) + Carbon Fiber (reinforcement layer)
Children’s Shoes/Casual Shoes: EVA (main body) + PETG Film (surface protection)