DA 3303 E hostanox P-EPQ 09.07 RZ

Nucleating Properties of
Hostanox P-EPQ
Figure 1 illustrates the clarifying effect
of Hostanox ® * P-EPQ ® measured
on injection molded polypropylene
plaques. After the addition of 0.1%
Hostanox P-EPQ, the haze is reduced
by 10 - 15 % compared to the control
sample, whereas P-2 and P-4 have
significantly weaker effects. This
clarity improvement remains nearly
unchanged during multiple extrusion
at 270 °C. Typical clarifiers like NA-1
can even lose their performance under
severe stress conditions (e.g. peak
temperatures, prolonged heat exposure
of the melt), eventually yielding
only marginally improved haze values
in the finished plastic articles.
The improved transparency achieved
just by addition of Hostanox P-EPQ
correlates with an increase of the
tensile strength (TS) and the crystallization
onset temperature (COT).
As shown in Figure 2, Hostanox P-EPQ
can improve the tensile strength by
approx. 10 % compared to the reference
(BS only), whereas the competitive
stabilizers have less effect on this
property. The processing stabilizer
Hostanox P-EPQ can act to a certain
extent as a nucleating agent. It can
improve the clarity of polypropylene
and enhance its mechanical properties.
Haze (%) after ...
50
40
30
20
10
0
BS only P-EPQ P-2
P-4
BS + NA-1
Procedure: Multiple Extrusion at 270 °C.
Specimens: 1 mm Injection Molded Plaques.
Figure 1: Haze of Polypropylene Plaques
1st Extrusion 3rd Extrusion 5th Extrusion
Additives: BS: 0.05 % AO-2 + 0.1 % CaSt;
0.1 % Processing Stabilizer each;
0.25 % Nucleating Agent NA-1.
Tensile Strength
(N/mm
30
150
2 ) TS COT
COT (°C)
20
10
0
BS only P-EPQ P-2
P-4 BS + NA-1
Procedure: Mechanical Testing and DSC
Performed after one Extrusion Pass
at 270 °C.
Specimens: 1 mm Injection Molded Plaques.
Additives: BS: 0.05 % AO-2 + 0.1 % CaSt;
0.1 % Processing Stabilizer each;
0.25 % Nucleating Agent NA-1.
Figure 2: Crystallization Onset Temperature (COT) and Tensile Strength (TS) of Polypropylene Random Copolymer
100
50
0
3