In the carpet industry, Nylon 6 and Nylon 66 are the two most widely used synthetic fibers. They belong to the same polyamide family but show distinct differences in performance and application scenarios due to inherent variations in their molecular structures. This article will break down the core differences between these two materials from a practical industry perspective.
1. Molecular Structure
The performance differences between Nylon 6 and Nylon 66 due to its various molecular structures.
Nylon 6: Formed by ring-opening polymerization of a single monomer, caprolactam (containing 6 carbon atoms), with a molecular chain repeating unit of -NH(CH₂)₅CO-. Each repeating unit contains only one amide bond. The hydrogen bonds in its molecular chain are loosely arranged with two binding modes, resulting in low molecular regularity and a relatively loose crystalline structure.
Nylon 66: Synthesized by polycondensation of two monomers, hexamethylenediamine (6 carbon atoms) and adipic acid (6 carbon atoms), with a molecular chain repeating unit of -NH(CH₂)₆NHCO(CH₂)₄CO-. Each repeating unit contains two amide bonds. The hydrogen bonds are arranged tightly in a linear manner, featuring high molecular regularity and a dense crystalline structure.
In simple terms, the molecular chains of Nylon 66 are "more neatly arranged and tightly bonded," while those of Nylon 6 are relatively "loose and flexible."
2. Comparison of core performance
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Nylon 6 |
Nylon 66 |
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Melting Point and Heat Resistance |
Melting point of 220℃, moderate heat resistance, prone to deformation under prolonged exposure to high temperatures (>100℃) |
Melting point of 260℃, high heat resistance, withstand short-time temperature above 120℃ |
|
Moisture Absorption |
Moisture absorption rate of approximately 4.5% under standard conditions, with moderate dimensional stability after water absorption |
Moisture absorption rate of approximately 3.5% under standard conditions, with minimal dimensional change after water absorption |
|
Dyeing Performance & Appearance |
Excellent dye mobility, uniform coloration and high color reproduction accuracy, easy to achieve color combination |
Slightly higher dyeing difficulty, need higher temperature and dye concentration, superior color stability |
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Deformation Resistance |
Low heat distortion temperature (approximately 60℃), prone to slight sagging under prolonged heavy pressure
|
High heat distortion temperature (approximately 80℃), with outstanding anti-pilling and anti-sagging performance |
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Cost |
Lower raw material and processing costs, outstanding cost-effectiveness |
Complex material synthesis process and higher processing temperature, higher price compared to Nylon 6 |
3. Selection Guide
Based on the differences in performance and cost, these two materials have formed distinct market positioning
- Nylon 6: Cost-effectiveness and Mid-range Choice
Due to the excellent processability, rich dyeing effects and cost-effectiveness, Nylon 6 has become the primary choice of residential and commercial use carpet.
Residential space: living room, bedroom, children's rooms(warm foot feel, diverse pattern option, meet the needs of daily light traffic
Commercial space: office building, hotel guest room, budget homestays carpet(controllable cost, can meet the regular service life requirements)
Special product: printed carpet, tufted carpet, multi-color blended carpet(outstanding dye uniformity and high pattern reproduction accuracy
- Nylon 66: high performance choice
Because of the high strength, wear resistance and weatherability, Nylon 66 focuses on high-end commercial scenarios
High-traffic area: airport terminal, shopping mall, exhibition centers and hotel lobbies(resistant to trampling and sagging, with a service life 1.5-2 times longer than that of Nylon 6)
High-end customization: full-house carpet for villas, VIP areas of star hotels and lobbies of luxury office buildings(distinctive quality, extended maintenance cycles, lower replacement costs)
In summary, the essences of Nylon 6 and Nylon 66 are "cost-effectiveness and general performance" and "high-end performance and quality". Customers should select the material according to the product position, application scenario and cost budgets, while buyers can reverse-judge material suitability through usage scenarios (foot traffic intensity, ambient temperature) and quality requirements, achieving a "value-for-money" selection logic.
