Oil transformation
Surfactant types
default: hexadecane in water
Melting point: Tm=18
Group A:
Td(21.5)>Tm
C16EO10: HLB=12
C18EO10: HLB=12
C18EO20: HLB=15.3
Group B:
Td(18)~=Tm
C16EO2: HLB=5
C16SorbEO20: HLB=15.5
C18SorbEO20: HLB=14.9
Group C:
Td(12)<Tm
C16EO20: HLB=15.7
Td=11
Aspect ratio of different oil alkyl length(Fig.7)
C16: =12
C17: =1.3
Group D:
no transition
Short tail: C12-tail
C20-40EO40
C16EO50
Double bonds: C18dSorbEO20
supercooling: 5~10 degree
Other drop phases
Polar: harder to induce shape transf.
Other drop phase
Nonpolar: no signif. diff. compared to alkanes
alkenes
1-eicosene
alkycyclohexane: pentadecylcyclohexane
tritetradecylglyceride
1-Heptadecene
cooling rate(K/min)
d_ini = 31um
Fig. 8 & 9
1.4: all drops --> flat hexagonal platelets -->freeze as solid hexagonal platelets
<1: --> tetragonal platelets dominant and rod-like asperities appear and grow from the platelet tips with acute angles
<0.5: tetragonal platelets --> ellipsoidal drops release thin fibers
<0.2: all drops--> final stages: either triangular platelets with rod-like asperities or ellipsoidal drops releasing thin fibers
Initial drop sizes
(0.44K/min)
Fig. 10
d_ini = 7 & 10 um: AR=30 -->100
d_ini > 15 um: AR=4.5
Estimated threshold for transformation beyond platelets: 13 um
lower cooling rate, higher critical size
C16-18EO25: HLB=16
CTAB
SOS(sodium octadecyl sulfates, C18)
Different alkane
(Nature)
tetradecane
heptadecane
Different alkane(Nature): eicosane
1-decanol(polar, C10)
C14: AR>400
STAB(2016Langmuir): Td = 23