Soybean Protein Fiber SPF Fiber

Wet Permeability and Moisture Vapor Transmission Characteristics

In order to test and compare these two properties of Soybean fibers, 6 jersey fabric samples were knitted with different 6 kinds of yarns, as illustrated in Table 1.

Table.1 the Type of Yarn Material

Type	Soybean yarns	PP Filament	PE Filament	PA Filament	PAN Yarns	Silk
Linear Density	18.8 tex	14.9tex/148f	16.5tex/ 34f	10tex/54f	18.8tex	13.3tex/30f

Table.2 Parameters of Samples

No.	Type of Yarn Material	Stitch Density /stitches/25cm²	Thickness /mm	Loop Length /mm	Area Density /g.m^-2
D₁	Soybean	4380	0.48	3.3030	100.6
D₂	PP	4503	0.42	3.1724	86.2
D₃	PE	4560	0.50	3.3333	90.6
D₄	PA	4320	0.55	2.8571	93.2
D₅	PAN	3953	0.53	3.1667	98.3
D₆	Silk	6745	0.56	3.0857	98.4

The wicking rates of first 10 min and the wetting areas of 1 min of all samples were tested, and the synthesized values of wet permeability were calculated, as illustrated in Table. 3.

Table.3 the Synthesized Values of Wet Permeability (Z)

No. of Samples	D₁	D₂	D₃	D₄	D₅	D₆
Z	4.46	10.1	10.77	0	1.9	0.116

Table 3 shows that the synthesized values of wet permeability of PP and PE samples are highest in all the samples. And the synthesized value of wet permeability of Soybean sample is lower than that of PP and PE, but higher than other samples. The sequence of wet permeability of these samples is listed as follows:

D₃>D₂>D₁>D₅>D₆>D₄

The water cup method was used to measure the quantities of permeated moisture vapor through the samples. In the experiment, the environment dry bulb temperature is 35° C, the wet bulb temperature 25° C, relative humidity is 35%, the test time is 2 hours, and the sample area is 32.75 cm². The tested quantities of permeated moisture vapor through the samples are listed in Table. 4.

Table.4 the quantities of permeated moisture vapor through the samples (g)

No. of Samples	D1	D2	D3	D4	D5	D6
the quantities of permeated moisture vapor	1.79	0.64	0.775	0.645	0.98	1.215

It is obvious that, from the data of Table.4, the moisture vapor transmission property of soybean sample is the best in all the samples. The sequence of the moisture vapor transmission property of these samples is listed as follows:

D₁>D₆> D₅> D₃> D₄> D₂

The wet permeability of Soybean is lower than that of PP and PE but higher than PAN, PA and silk; while the moisture vapor transmission property of soybean sample is better than silk, PP, PE, PA, PAN. Therefore, soybean fiber is a kind of comfortable fiber with relatively good wet permeability, excellent moisture vapor transmission property and dry touch.