| Summary: | 碩士 === 逢甲大學 === 紡織工程研究所 === 86 === In order to shorten the production time for producing and
spinning of rayon fibers by two days,many countries have been
working on the spinning technique of solution direct spun
cellulose fibers.This paper first discusses the solventthat
can dissolve fibers and the properties of the solvent.Then,the
dry-wet spinning technique is adopted to produce cellulose
fibers.In addition,there isfurther discussion which is about the
technique of blending the polymers of cellulose and
polyvinyl alcohol(PVA).The blended proportions of cellulose and
polyvinyl alcohol(PVA) are 90/10 Wt/Wt and 80/20 Wt/Wt.
Cellulose and the polymerblend are respectively put into a dry-
wet spinning machine at 90*.The fibers arepassed through the
processes of water washing and drying.The fibers are hot
drawnat 70* one or two ratios of times,1.83 and 7.01. The dry-
wet spinning of cellulose fibers and the polymer need an
evenly blended solution.The polymer concentration and viscose
solution are essential tothe solvent of the spinning.In this
paper,there is also a discussion of the materialwhich are
needed for this experiment.There are the polymer concentration,
the viscosesolution,and the structure,morphology, physical
properties of cellulose fibers and the polymer blended.Various
techniques such as viscose measurements,tenacity measurements,
SEM observation,TGA,X-ray and hot water treament,were adopted.
The results of viscosity measurements reveal that the range
of cellulose viscosityis between 68000~61000cp.
Viscosity varies in accordance with temperature and polymer
concentration.The test of tenacity of fibers indicates that the
tenacity will increase with the increase of the drawn rate.
However,the increase of PVA will reducethe tenacity.The SEM
shows that the fiber cross section was nearly a circle.Afterthe
test of hot water treament,the middle part of the fiber cross
section is damaged.We deduce that the interaction between
cellulose and PVA is weak.By the wide angle X-ray diffraction
pattern,we find that the circle of the cross section changes
gradually into symmetrical arches. From WAXD data,the
regenerated cellulose fibersspun from NMMO solution gave the
cellulose 2 crystalline unit cell.
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