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The various kinds of PTFE fibers were added into POM to
increase the wear resistance and to decrease the frictional
coefficient of POM. However, PTFE has a low surface energy,
resulting in weak adhesion donding and the decrease of
mechanical properties. To enhance the adhesion between the
matrix and fiber, the author used argon plasma to treat the
surface of PTFE fiber(PPTEF) and then the AAm was graffted onto
the surface of PPTFE fiber(AAm-g-TFE). The experiment
parameters in this investigation were RF ower of plasma, plasma
treatment time, concentration of grafting monomers,and
grafting time. The results obained were as followes:
1. The self-designed rotary plasma equipment could efficiently
to modify the PTFE fibers as the same as PTFE films in wo
parallel Cu disk before, resulting producing C=C, oxygen-
containing groups and croslinking on the surface which could
be comfirmed by FTIR using PR method and XPS measurement. 2.
From SEM photographs and the spectrum of FTIR, low RF power of
plasma treatment could modify PTFE fibers efffectively. On
the contrary, higher RF power such as exceeding 60W lead to
unveiling of fresh PTFE, which decreased the effect of
modificattion. 3. PTFE fibers treated by low RF power of
plasma treatment both decreased the frictional coefficient
and Taber wear factor as a result of the improvement of
adhesion between PTFE fiberss and a result of the imporvement of
adhesion between PTFE fibers and POM mattrix. However, free
radicals, oxidation and eroxides produced by lasma treatment
processing would destroyed the strctre of POM matrix, and lead
to decrease of mechanical properties of POM/PTFE composites.
4. From the spectrum of FTIR and XPS of AAm-g-PPTFE fibers, the
degree of grafting AAm was direct proportion to grafting
concentration and grafting time, and PPAM formed a thin film
on the surface of TFE fiber according to SEM photographs of
AAm-g-PPTFE fibers. 5. According to the length of ull-out and
holes between POM and fibers on the fractured surfaced
surface, the sequence of strength of adhesion between matrix and
fibers was POM/ AAm-g-PPTFE > POM/PPTFE > POM/PTFE. 6. As
a result of PAAm of forming on the surface of PPTFE fibers was
harmful to slide application, frictional coefficient and
Taber wer factor of POM/AAm-g-PPTFE composites increased
with increasing grafting time. 7. The adhesion between POM
and fiber had been enhanced by using plasma to treat the PTFE
fiber and then AAm grafting. As a result the elongation and
impact strength of POM/AAm-g- PPTFE were increased.
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