Initially, both DTBP
and TBPA were evaluated as free radical initiators to produce PVDF using supercritical carbon dioxide as a reaction medium.
More styrene also meant more of the initiator DTBP
was added since DTBP
was used at 8 wt% based on styrene.
A Fundamental Study of the Oxidation Behavior of SI Primary Reference Fuels with Propionaldehyde and DTBP
as an Additive.
The results in Table 4 also suggest that the peroxides DCP and DTBP do not produce a large degree of LCB in the PP backbone.
The use of DCP and DTBP also resulted in considerable improvement of melt strength, but their efficiencies were much smaller than BPO or CHP.
From the value of half-life time of different peroxides, as shown in Table 1, it can be inferred that the order of the decomposition temperature for investigated peroxides is as follows: BCHPC < BPO < DCP < DTBP < CHP.
HPLC analysis of the other samples also gave complex products among which DTBP was always detected.
This apparent increase in concentration is actually due to the release of DTBP, from the hydrolytic decomposition of the phosphite.
Figure 4 shows the experimental data from solubility experiments on 168, 168PO and DTBP in the PP film presented as plots of ln [phi] v 1/T.
The Arrhenius parameters of the decomposition of the DTBP in LDPE determined by kinetic studies (16) were used to calculate the time needed to dissociate the initiator, because this decomposition rate is affected by the media in which the peroxide is immersed and the radical concentration is a primary variable of this reaction (5-8).
DTBP = 2,5 Dimethyl 2,5 bis di(tert-butyl) peroxy-hexane.