一、Comparison of material properties
Peculiarity | Nylon | Polyester |
Chemical composition | Polyamide(PA) | Polyethylene terephthalate(PET) |
Intensity | High tensile strength, excellent wear resistance | Higher strength, but slightly lower than nylon |
Weight | Higher density(1.14-1.15 g/cm³) | Lighter(1.38 g/cm³) |
Hydroscopicity | Strong hygroscopicity (about 4%), easy to absorb water in humid environment | Good hydrophobicity (water absorption 0.4%), quick drying |
Heat resistance | Melting point about 220°C, high temperature easy to soften | Melting point 260°C, better heat resistance |
Ultraviolet resistance | Long time exposure to the sun is prone to yellowing and aging | Strong UV resistance |
Environmental protection property | Recyclable but dependent on chemical technology | The technology of recycled polyester (rPET) is mature |
Cost | High raw materials and processing costs | Low cost, suitable for mass production |
二、Comparison of advantages and disadvantages
- Nylon
- High strength and wear resistance:Suitable for high-load scenarios (such as hiking bags, military backpacks).
- Good flexibility:Soft fabric, fit the body or object shape.
- Tear resistance:The fiber has strong elasticity and is not easy to be pierced by sharp objects.
- Easy water absorption:Humid environments can add weight and breed mold.
- High cost:Raw materials and processing technology are complex, and the price is higher than that of polyester.
- Not UV resistant:Long-term outdoor use needs to add coating protection.
- Polyester
- Lightweight:Reduce the weight of the bag, suitable for daily commuting or light travel bag.
- o Anti-wrinkle and form-preserving:Long-term use is not easy to deform, keep the bag clean appearance.
- Low cost:Suitable for mass market, cost-effective.
- Poor air permeability:Long time contact is hot, not suitable for close-fitting bags.
- Electrostatic adsorption:Dust is easily absorbed, and ESD treatment is required.
- Degradation difficulty:Traditional polyester relies on petrochemical raw materials, and environmental protection is controversial.
三、Application scenario analysis
- Nylon application scenario
- Hiking bag:Nylon’s high strength and tear resistance can handle rock friction and heavy loads (such asOsprey‘s nylon hiking bag).
- Diving bag/waterproof bag:Improve water resistance by using coating technologies such as TPU to compensate for water absorption defects.
- High-end functional bags:
- Military/Tactical package:Extreme durability is required, such as the 11 Tacticalmilitary backpack.
- Suitcase:High-density nylon (such as Cordura®) is used in high-end impact-resistant housing (such as Tumi).
- Polyester application scenario
- Daily commute with light travel:
- Student backpack, commuter tote bag:Lightweight and low cost (such as Herschel‘s polyester backpack).
- Folding storage bag:Anti-wrinkle properties are easy to fold and carry.
- Stylish and eco-friendly bags:
- Recycled polyester eco-friendly bag:Patagonia‘s rPET collection, for example, is both lightweight and sustainable.
- Imitation leather bag:Ultrafine polyester imitation leather (such as UltraSuede®) for affordable fashion handbags.
- Short-term outdoor activities:
- Riding bag, picnic bag:A low cost waterproof coating is just what you need.
四、Selection suggestion
- Pursue durability and professionalism:Choose nylon (such as mountaineering, military, high-end travel scenarios).
- Focus on lightness and cost performance:Choose polyester (e.g. daily commute, fast fashion, short-term outdoors).
- Environmental requirements:Preferred recycled polyester (rPET) or biokinisaurus (such as Econyl®).
五、Future trend
- Nylon upgrade:Enhance environmental protection by adding carbon fiber for strength, or developing bio-Kinisaurus (such as castor oil extraction).
- Polyester innovation:Expand the high-end market by combining smart coatings (temperature control, self-cleaning) and modular design.
- Mixed materials:Nylon + polyester blends(such as Codura® NYCO)are a compromise that balances performance with cost.
Sum up
Nylon and polyester are irreplaceable in the bag industry: Nylon wins for performance, Suitable for extreme environment; Polyester is good at cost performance, Dominate the mass market.