Materials for Turbine Power Blades, Reinforcements, and Resins - Hybrid Anisotropic Materials for Wind Power Turbine Blades - page 84

LM20% St
LM25% St
LM30% St
HM30% St
HM35% St
HM40% St

10000

1000

100

300 310 320 330

1/Temperature, (ÞC)

340 350 360

FIGURE 3.14
Plot.of.log.η.versus.1/T.for.different.vinyl.ester.resins.

TABLE 3.15
Constants.A.and.B.in.the.Andrade.
Equation.for.Various.Vinyl.Ester.Resins
VinylEsterResinswithMn=690g/mol
Wt%Styrene LogA B

20 -9.198 3995

25 -8.540 3660

30 -6.89 2983

Vinyl Ester Resins with Mn = 1,000 g/mol
30 -7.99 3752

35 -8.67 3795

40 -6.13 2758

3.9.5 Effect of Molecular Weight

Unlike.dilute.solutions,.concentrated.polymer.solutions.show.a.great.deal.of.
interaction.between.the.macromolecules..For.a.concentrated.solution,.prop-
erties. above. and. below. Mc,. the. critical. molecular. weight. for. chain. entan-
glement,.may.be.quite.different..The.dependence.of.viscosity.on.molecular.
weight.changes.from.around.unity.below.Mc.to.around.3.4.to.3.5.above.Mc.
indicated.in.equation.(3.7).and.equation.(3.8). 38-40

η=.KM.....below.Mc. (3.7)