Comprehensive Guide to Shoe Soles

1. Leather Soles:

Leather soles are breathable and allow the feet to naturally breathe. They are highly breathable, preventing discomfort and maintaining foot dryness by releasing absorbed sweat. Typically made from cowhide, leather soles are more expensive. They are known for their ability to maintain shape, elasticity, comfort, and shock absorption, reducing fatigue and promoting airflow while absorbing moisture. However, they are vulnerable to water and oil exposure, which may cause warping, deformation, or decay. Key characteristics:

Good thermal insulation, keeping feet at a comfortable temperature.

Lightweight, with a density of 0.95–1.05 grams per square centimeter, similar to water density. It can be waterproof and releases moisture once the shoe is no longer damp, ensuring comfort.

Unique three-dimensional fiber structure that bends at 180 degrees without breaking. It adapts quickly to the shape of the foot, effectively absorbing ground impact, offering better foot protection than other materials of the same thickness.

2. Rubber Sole (RB):

RB is an abbreviation for rubber; it is heat-pressed and comes in natural and regenerated rubber forms. It is heavy, not oil-resistant, and requires roughening of the bonding surface during molding. The rubber is prone to shrinkage when heated, and its color may vary.

Advantages: Good abrasion resistance, slip resistance, elasticity, and durability. Softness, good extensibility, and stability; good hardness and bendability, waterproof. Disadvantages: Heavy, prone to frosting (a quality issue), poor corrosion resistance (environmental concerns), soft and easily punctured, poor breathability and moisture absorption, and unsuitable for oil-rich environments like gas stations.

3. Polyurethane Sole (PU):

Polyurethane (PU) is a high molecular material made from A/B/C polyester foams, available in oil-based and water-based forms. It is a popular material for high-end leather shoes, sports shoes, and travel shoes.

Advantages: Low density, soft texture, excellent elasticity, comfort, and lightness; outstanding resistance to oxidation, abrasion, and bending; high hardness, excellent shock absorption, slip resistance, and chemical resistance; environmentally friendly, resistant to wrinkles. Disadvantages: High water absorption, easy yellowing, prone to cracking, poor extensibility, water damage, and poor breathability.

4. EVA Sole:

Ethylene Vinyl Acetate (EVA) is a lightweight, easy-to-process polymer used in running shoes, casual shoes, and training shoes. It is not very durable and is sensitive to oil.

Advantages: Lightweight, elastic, flexible, excellent colorability, and suitable for various climates. Disadvantages: Prone to water absorption, non-environmentally friendly, easy to get dirty.

5. MD Sole:

MD (also known as Phylon) is a secondary high-pressure EVA molding product, typically consisting of EVA combined with rubber or other materials.

Advantages: Lightweight, elastic, sleek appearance, easy to clean, good hardness, density, and tensile strength. Disadvantages: Poor corrosion resistance, reduced shock absorption over time, low breathability.

6. TPR Sole:

TPR (Thermoplastic Rubber) is a new type of polymer shoe material with the performance of rubber but can be processed like thermoplastic plastic. It is produced by molding heated TPR pellets.

Advantages: Easy to mold, affordable, lightweight, comfortable, high elasticity, good breathability, excellent low-temperature resistance, and high friction coefficient for strong grip. Disadvantages: Heavy, poor wear resistance, low flexibility, poor shock absorption, and low breathability.

7. TPU Sole:

Thermoplastic Polyurethane (TPU) is a new eco-friendly material made from isocyanates and polyols. It provides excellent mechanical strength, wear resistance, and oil resistance.

Advantages: Exceptional wear resistance, mechanical strength, high-quality appearance, and durability. Disadvantages: Poor heat resistance, low heat water resistance, prone to yellowing, harder, heavier, and low breathability.

8. PVC Sole (Synthetic Leather):

Polyvinyl Chloride (PVC) is a translucent, glossy material prone to whitening at bending points.

Advantages: Affordable, resistant to oil, abrasion, and insulation. Disadvantages: Poor slip resistance, poor texture, low resistance to cold, inflexibility, and poor breathability.

9. TR Sole:

TR (Thermoplastic Rubber) is an improved version of TPR, combining TPE and rubber, offering better overall performance.

10. Faux Leather Sole:

A combination of rubber and plastic, this sole mimics natural leather with a textured appearance. It is light, comfortable, and noise-free, providing good flexibility and hardness but lacks the breathability and moisture absorption of natural leather.

11. BPU Sole:

BPU is a modified type of PU material known for its environmental benefits, low density, and smooth surface. It is lightweight, durable, and suitable for footwear applications.

12. Cowhide Sole:

Made from thermoplastic elastomers, this sole mimics the durability of cowhide, with good elasticity and wear resistance. It is commonly used for daily wear shoes and outdoor footwear.

13. Phenolic Resin Sole:

A type of rubber sole that undergoes a different processing method, providing an affordable option for footwear.

14. Raw Rubber Sole:

Unrefined rubber, used as the base material for soles, is known for its lower density and durability. The processed form is more resilient and wear-resistant.

15. PC Sole:

Polycarbonate (PC) is a thermoplastic material known for its impact resistance, dimensional stability, and high transparency. It is highly durable and offers aesthetic appeal.

16. ABS Sole:

Acrylonitrile Butadiene Styrene (ABS) offers excellent impact resistance and mechanical properties, though it has lower heat resistance and weatherability.

17. PE Sole:

Polyethylene (PE) has excellent corrosion resistance and electrical insulation properties, offering good flexibility and wear resistance.

18. PP Sole:

Polypropylene (PP) is a strong polymer with excellent durability, low density, and high heat resistance.

19. SBR Sole:

Styrene Butadiene Rubber (SBR) is a versatile material used in shoes, offering good mechanical properties, heat resistance, and wear resistance.

20. Cork/Wood Sole:

A natural option for eco-friendly shoes, offering a unique texture and durable design.

21. Other Materials:

A combination of materials like SBR, TPR, ABS, PVC/EVA/PU regrind, and natural fibers like jute and wool.