. It was concluded that the anticorrosion
efficiency of the organic coating with this pigment was highest at
PVC = 2% and 3%.
The organic coatings with PANI-CAS as the pigment attained
a high anticorrosion efficiency at PVC = 0.1–2%. Corrosion on the
panel surface was ≤0.3%and corrosion in the cut was 0.5–1 mm. The
occurrence of blisters on the panel surface at these PVC levels was
lower than for the non-pigmented organic coating. The anticorrosion
efficiency, however, decreased at PVC > 3% and became poorer
with increasing PVC. None of the organic coatings attained anticorrosion
efficiency as high as that exhibited by the non-pigmented
organic coating.It follows from the above results that presence of the conductive
polyaniline compound in the organic coating brings about
increased anticorrosion resistance if the PVC is kept adequately
low, but this effect is reduced at high PVC levels. The latter phenomenon
can be explained in terms of a decrease in the barrier
effect in the organic coating with a high conductive polyaniline
compound content. This is associated with increased permeability
of the organic coating for the aggressive environment, resulting
in a rapid attack on the initially protected substrate. This fact has
also been reported in other publications devoted to the anticorrosion
efficiency of conductive polyaniline compounds [30]. The
PVC, however, is not the sole parameter affecting the anticorrosion
efficiency of an organic coating; the type of the dopant present
in the conductive polyaniline compound is an important factor as
well.
Fig. 3 shows organic coating and a steel panel after 1440 h of
exposure in a salt mist atmosphere.
The results of the tests examining the resistance of these organic
coatings to an atmosphere with SO2 are summarised in Table 5.
The exposure time was 2208 h. Four types of corrosion effects,
appearing to different extents depending on the PVC as well as on
the dopant type, were examined.The organic coatings with PANI-H3PO4 as the pigment attained
a high anticorrosion efficiency at PVC = 0.1–5%. Corrosion on the
panel surface was ≤1% and corrosion in the cut was 4–4.5 mm.
Corrosion on the panel surface increased with increasing PVC at
PVC ≥ 10%. The occurrence of blisters both on the panel surface and
in the cut was lower with a higher PVC. The coating with PVC = CPVC
was an exception, where the occurrence of blisters was high and
corrosion on the panel surface reached 100%. The non-pigmented
organic coating exhibited appreciable corrosion on the panel surface,
viz. 10%. It was concluded that the anticorrosion efficiency of
the organic coating with this pigment was highest at PVC = 1%.
The organic coatings with PANI-H2SO4 as the pigment exhibited
10% corrosion on the panel surface, which is comparable to
that found for the non-pigmented organic coating. This corrosion
increased further with increasing PVC at PVC ≥5%. The use of this
pigment did not improve the organic coating’s resistance in this
cyclic corrosion test.
The organic coatings with PANI-HCl as the pigment attained
a high anticorrosion efficiency at PVC = 0.1–5%. Corrosion on the
panel surface did not exceed 3%, and corrosion in the cut was
2–2.5 mm. Corrosion on the panel surface was lower than that
found for the non-pigmented organic coating, but occurrence of blisters in the cut and on the surface attained comparable levels
at these PVCs. If the PVC was increased to 10% or higher,
corrosion on the panel surface exhibited an increasing trend
with increasing PVC. It was concluded that the anticorrosion efficiency of the organic coating with this pigment was highest at
PVC = 0.1–1%.
. It was concluded that the anticorrosionefficiency of the organic coating with this pigment was highest atPVC = 2% and 3%.The organic coatings with PANI-CAS as the pigment attaineda high anticorrosion efficiency at PVC = 0.1–2%. Corrosion on thepanel surface was ≤0.3%and corrosion in the cut was 0.5–1 mm. Theoccurrence of blisters on the panel surface at these PVC levels waslower than for the non-pigmented organic coating. The anticorrosionefficiency, however, decreased at PVC > 3% and became poorerwith increasing PVC. None of the organic coatings attained anticorrosionefficiency as high as that exhibited by the non-pigmentedorganic coating.It follows from the above results that presence of the conductivepolyaniline compound in the organic coating brings aboutincreased anticorrosion resistance if the PVC is kept adequatelylow, but this effect is reduced at high PVC levels. The latter phenomenoncan be explained in terms of a decrease in the barriereffect in the organic coating with a high conductive polyanilinecompound content. This is associated with increased permeabilityof the organic coating for the aggressive environment, resultingin a rapid attack on the initially protected substrate. This fact hasalso been reported in other publications devoted to the anticorrosionefficiency of conductive polyaniline compounds [30]. ThePVC, however, is not the sole parameter affecting the anticorrosionefficiency of an organic coating; the type of the dopant presentin the conductive polyaniline compound is an important factor aswell.Fig. 3 shows organic coating and a steel panel after 1440 h ofexposure in a salt mist atmosphere.The results of the tests examining the resistance of these organiccoatings to an atmosphere with SO2 are summarised in Table 5.The exposure time was 2208 h. Four types of corrosion effects,appearing to different extents depending on the PVC as well as onthe dopant type, were examined.The organic coatings with PANI-H3PO4 as the pigment attaineda high anticorrosion efficiency at PVC = 0.1–5%. Corrosion on thepanel surface was ≤1% and corrosion in the cut was 4–4.5 mm.Corrosion on the panel surface increased with increasing PVC atPVC ≥ 10%. The occurrence of blisters both on the panel surface andin the cut was lower with a higher PVC. The coating with PVC = CPVCwas an exception, where the occurrence of blisters was high andcorrosion on the panel surface reached 100%. The non-pigmentedorganic coating exhibited appreciable corrosion on the panel surface,viz. 10%. It was concluded that the anticorrosion efficiency ofthe organic coating with this pigment was highest at PVC = 1%.The organic coatings with PANI-H2SO4 as the pigment exhibited10% corrosion on the panel surface, which is comparable tothat found for the non-pigmented organic coating. This corrosionเพิ่มเติม ด้วย PVC PVC ≥5% การใช้งานนี้เม็ดสีไม่ได้ปรับปรุงความต้านทานของสีอินทรีย์ในที่นี้การทดสอบการกัดกร่อนวงจรเคลือบสารอินทรีย์ ด้วย PANI HCl เป็นเม็ดสีได้anticorrosion ประสิทธิภาพสูงที่ PVC = 0.1 – 5% การกัดกร่อนในการพื้นผิวแผงไม่เกิน 3% และการกัดกร่อนในการตัดก็2 – 2.5 mm. การกัดกร่อนบนแผง พื้นไม่ต่ำกว่าพบไม่ได้พ่นสีสีอินทรีย์ แต่เกิดแผล บนผิวน้ำ และ ในการตัดได้ระดับเทียบเท่าในรูปเหล่านี้ ถ้า PVC เพิ่มขึ้น 10% หรือสูงก ว่าการกัดกร่อนบนผิวแผงจัดแสดงแนวโน้มการเพิ่มขึ้นด้วย PVC มันถูกสรุปว่า ประสิทธิภาพ anticorrosion เคลือบอินทรีย์ด้วยเม็ดสีนี้ได้สูงสุดที่พีวีซี = 0.1 – 1%
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