Sustainability Approach of Recycled Denim Fabrics with a Life Cycle Assessment

Fig. 1.

Fig. 2.

Percentage improvement results of life cycle analysis

% improvement	Abiotic depletion	Abiotic depletion (fossil fuels)	Global warming	Ozone layer depletion	Human toxicity	Toxic effect on freshwater
R
D1	9.75	7.28	7.16	4.82	8.09	10.76
D2	12.33	8.90	8.97	6.18	10.21	13.89
D3	14.36	10.17	10.38	7.24	11.87	16.35
D4	16.75	11.67	12.06	8.50	13.84	19.25
D5	18.96	13.05	13.60	9.66	15.65	21.93

Properties of yarns

Samples	Warp Yarn	Weft Yarn
Reference (R)	Ne 6.5/1 Open End 30% Recycle / 70% Cotton	Ne 13/1 90% Cotton+7.5% Polyester+2.5% Elastane Modified Ring
D1		Ne 13/1 50% Cotton+40% Recycle Cotton+7.5% Recycle Polyester+2.5% Elastane Modified Ring
D2		Ne 13/1 40% Cotton+50% Recycle Cotton+7.5% Recycle Polyester+2.5% Elastane Modified Ring
D3		Ne 13/1 30% Cotton+60% Recycle Cotton+7.5% Recycle Polyester+2.5% Elastane Modified Ring
D4		Ne 13/1 20% Cotton+70% Recycle Cotton+7.5% Recycle Polyester+2.5% Elastane Modified Ring
D5		Ne 13/1 10% Cotton+80% Recycle Cotton+7.5% Recycle Polyester+2.5% Elastane Modified Ring

Physical properties of fabrics

Sample Number	Unit weight (gr/m2)		Weft per inch		Warp per inch		Thickness (mm)
	Mean	Std.dev.	Mean	Std.dev.	Mean	Std.dev.	Mean	Std.dev.
R	377	2	46	0	67	0.816497	0.754	0.005
D1	385	1	46	0	74	1.632993	0.768	0.007
D2	388	1,73	47	1.632993	69	0	0.764	0.005
D3	378	3	46	0.816497	68	0	0.752	0.004
D4	379	2,64	45	1.414214	65	0.816497	0.760	0.006
D5	382	3,46	47	1.632993	71	0.816497	0.782	0.007

Selected thermal comfort properties of denim fabrics

Sample number	Relative water vapor permeability (%)		Water vapor permeability (WVPR)		Thermal resistance (m2K/W)
	Mean	Std.dev.	Mean	Std.dev.	Mean	Std.dev.
R	52.42	0.94	4.71	0.45	0.003839	0.000134
D1	49.32	0.66	5.06	0.18	0.004068	0.000278
D2	48.18	1.28	5.46	0.24	0.004384	0.000116
D3	46.53	0.99	5.80	0.26	0.004553	0.001127
D4	46.46	0.67	5.50	0.20	0.004900	0.000898
D5	46.96	1.46	5.62	0.26	0.004944	0.000097

Tensile and tear strength results of denim fabrics

Sample Number	Tensile strength (Kgf) (weft direction)		Tensile strength (Kgf) (warp direction)		Tear strength (gf) (weft direction)		Tear strength (gf) (warp direction)
	Mean	Std.dev.	Mean	Std.dev.	Mean	Std.dev.	Mean	Std.dev.
R	46	2.44	92	2.54	4957	162.39	6300	148.76
D1	43	3.39	90	2.54	4708	34.28	6083	135.79
D2	41	2.73	88	2.12	4657	80.76	5914	68.84
D3	39	2.64	88	2.34	4201	61.05	5817	123.93
D4	38	2.91	85	5.19	3945	66.64	5776	134.53
D5	36	3.39	87	4.74	3613	104.82	5903	120.89

Yarn properties

Samples	%Um	% CVm	Index	H	sh	Breaking force (gF)	Breaking elongation (%)	Rkm (kgf×Nm)	B-work (gF cm)
R	8.58	10.86	1.87	6.28	1.35	1019.84	8.08	17.27	2083.26
D1	6.75	8.52	1.49	6.86	1.63	814.68	11.98	16.56	2064.00
D2	8.12	10.28	1.80	7.39	1.75	746.88	11.30	15.18	1292.89
D3	8.79	11.19	1.95	7.52	1.91	745.33	11.68	15.15	1350.68
D4	10.61	13.78	2.41	8.14	2.06	652.90	9.57	13.27	1903.17
D5	10.84	13.56	2.37	8.58	2.22	646.03	9.06	13.13	1845.35

Tests applied to denim fabrics

Test No	Test name	Test Standard
1	Standard Test Methods for Mass Per Unit Area (Weight) of Fabric	ASTM D3776: 2020
2	Standard Test Method for Breaking Strength and Elongation of Textile Fabrics (Grab Test)	ASTM D5034: 2021
3	Standard Test Method for Tearing Strength of Fabrics by Falling-Pendulum (Elmendorf-Type) Apparatus	ASTM D1424: 2021
4	Standard Test Methods for Stretch Properties of Fabrics Woven from Stretch Yarns	ASTM D3107: 2019
5	Textiles - Physiological effects - Measurement of Thermal and Water-Vapor Resistance under Steady-State Conditions (Sweating Guarded-Hotplate Test)	TS EN ISO 11092: 2014
6	Textiles the Assessment of Drape of Fabrics.	TS 9693: 1991

Selected performance properties of denim fabrics

Sample number	Elasticity (%)		Air permeability (mm/s)		Stiffness (Kgf)
	Mean	Std.dev.	Mean	Std.dev.	Mean	Std.dev.
R	42	1.58	56.491	1.497	0.784	0.106
D1	39	2.23	53.887	3.045	0.802	0.080
D2	38	2.54	52.525	1.852	0.795	0.027
D3	38	2.34	57.142	1.654	0.718	0.017
D4	37	2.12	60.118	2.705	0.790	0.027
D5	36	1.87	51.207	2.104	0.713	0.101