Nylon

Material Composition Assumptions

The default CCI score covers nylon fibre (polyamide), representing 1 kg of nylon yarn at the gate of the fibre producer. Two primary nylon types dominate the apparel market:

• Nylon 6,6: Produced from adipic acid and hexamethylenediamine (HMDA), both derived from cyclohexane (a petroleum derivative). Adipic acid production historically generated large N2O emissions (a potent GHG with GWP100 of 265-298). Modern facilities with catalytic abatement have reduced but not eliminated this source.
• Nylon 6: Produced from caprolactam, derived from cyclohexanone via the Beckmann rearrangement. Does not involve adipic acid and therefore avoids the N2O burden, resulting in a modestly lower footprint (~7-8 kgCO2e/kg vs. ~10-12 kgCO2e/kg for nylon 6,6 without abatement).

The default blended estimate of ~9 kgCO2e/kg assumes a mix of modern nylon 6 and nylon 6,6 production with partial N2O abatement, as is typical of current major producers in China, South Korea, and Taiwan.

Upstream petrochemical feedstock (benzene, cyclohexane) accounts for ~10% of total emissions and is classified as Scope 3 extraction and refining.

Manufacturing Geography

The default manufacturing region reflects the global structure of polyamide fibre production:

• China: Dominant producer of nylon 6 fibre (particularly Fujian and Zhejiang provinces). Grid intensity ~565 gCO2e/kWh.
• Taiwan: Major producer of nylon 6,6 for performance apparel (e.g., INVISTA, Formosa Chemicals). Grid intensity ~510 gCO2e/kWh.
• South Korea: Significant caprolactam and nylon 6 production capacity. Grid intensity ~450 gCO2e/kWh.
• USA: INVISTA operates large nylon 6,6 facilities; primary market is industrial and carpet applications, with some apparel fibre. Grid intensity ~390 gCO2e/kWh.

The most important emission driver — N2O from adipic acid — is a process emission independent of grid source. Modern Chinese facilities vary in the extent of N2O abatement installed, making China-sourced nylon 6,6 more variable in footprint than European or US production (where abatement is near-universal).

Regional Variation

Production Region	Grid Intensity	Estimated Score Adjustment
China (default)	~565 gCO2e/kWh	Baseline
Taiwan	~510 gCO2e/kWh	-10% on Scope 2 (saves ~0.2 kgCO2e)
South Korea	~450 gCO2e/kWh	-20% on Scope 2 (saves ~0.4 kgCO2e)
USA	~390 gCO2e/kWh	-31% on Scope 2 (saves ~0.6 kgCO2e)
EU (with N2O abatement)	~300 gCO2e/kWh	-47% on Scope 2 + lower N2O (saves ~1.5-2.5 kgCO2e total)

Note: Because Scope 3 (petrochemical feedstock, caprolactam synthesis) dominates at ~70% and N2O process emissions are feedstock-dependent rather than grid-dependent, regional grid variation alone has a modest effect on the total score. N2O abatement status is the more impactful variable.

Provenance Override Guidance

A supplier or manufacturer may override the default CCI score by submitting:

1. Product Carbon Footprint (PCF) certified per ISO 14067 or PAS 2050, with explicit disclosure of N2O abatement technology and verified emission factor for adipic acid or caprolactam production.
2. Bluestar or ECONYL documentation: Recycled-content nylon (e.g., ECONYL from Aquafil, using post-consumer fishing nets and carpet waste) has a substantially lower footprint of approximately 3-4 kgCO2e/kg and qualifies as a provenance override.
3. Supplier energy data: Utility records or renewable energy certificates (RECs) for polymerization and texturing facilities.
4. N2O abatement records: Third-party-verified emission monitoring data confirming installed catalytic abatement efficiency (>90% destruction rate).
5. bluesign or OEKO-TEX certification may accompany process data but does not alone constitute a PCF override.

Methodology Notes

• CCI score of 9 kgCO2e/kg reflects a blended estimate for modern Asian production with partial N2O abatement. Pre-abatement nylon 6,6 could exceed 18-20 kgCO2e/kg due to unmitigated N2O. Post-abatement EU production is typically 6-8 kgCO2e/kg.
• Scope breakdown: Scope 3 dominates at ~67% (6 kgCO2e), comprising petrochemical feedstock extraction and refining, caprolactam synthesis energy and reagents, and upstream logistics. Scope 2 is ~22% (2 kgCO2e) from polymerization and texturing electricity. Scope 1 is ~11% (1 kgCO2e), primarily residual N2O from adipic acid production after abatement.
• Functional unit: 1 kg of nylon (polyamide) multifilament yarn, cradle to gate (extraction through yarn production).
• N2O accounting: N2O has a GWP100 of 265 (AR5) or 273 (AR6). Even small quantities of unabated N2O contribute meaningfully to the total. The default estimate assumes ~75% abatement efficiency across the modelled production mix.
• Recycled nylon: ECONYL and similar recycled nylon products are outside scope of this default entry. A separate entry or provenance override is required for recycled-content claims.
• Comparison context: Nylon’s footprint (~9 kgCO2e/kg) is higher than conventional polyester (~5.5 kgCO2e/kg) due to the N2O burden and more complex synthesis routes, but substantially lower than wool (~25 kgCO2e/kg). Nylon’s durability and performance characteristics in technical apparel must be considered in functional-unit comparisons.
• Data gaps: N2O abatement rates at Chinese facilities are not uniformly disclosed, introducing uncertainty of ±20-30% around the central estimate. This is the primary reason for the medium confidence rating.