Chemistry Reference
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and DCPD-UPR-TO20, respectively. The obtained DCPD-UPR and DCPD-
UPR-TO polymer products were blended with styrene and hydroquinone at
90 1C for 1 h to give liquid resins that were light yellow or yellow.
8.2.3 Synthesis of UPR/COPERMA Blends
The synthesis of COPERMA was similar to that of TOPERMA, which followed
the procedures described in ref. 8. The COPERMA product (Scheme 8.4) was
a light-yellow soft solid at room temperature. The acid value of COPERMA
was 255 mg KOH g
1
. In order to make the COPERMA solid product easily
add into the UPR, the product was first mixed with 35 wt% styrene. There-
after, the obtained COPERMA/styrene resin was added to a commercial UPR
(containing 35 wt% styrene) readily to produce UPR/COPERMA resins at
room temperature. The contents of the COPERMA resin in the UPR/
COPERMA blends were 0, 5, 10, 15 and 20% by weight, thus the corres-
ponding samples were labeled as UPR, UPR/COPERMA5, UPR/COPERMA10,
UPR/COPERMA15, and UPR/COPERMA20, respectively.
8.2.4 Curing of the Oil-based UE Monomers or UPEs with
Styrene
The TOPERMA product was cured with styrene as follows: first, TOPERMA
was blended with a specified amount of styrene by stirring under N
2
atmosphere for 1 h at 70-80 1C. The viscosity of the TOPERMA resin con-
taining 33 wt% styrene was 1050 mPa
s. Then the resin was mixed with the
initiator tert-butyl peroxy benzoate at 2% of the resin weight and degassed
for 10 min. After that, the resin was poured into molds and placed in
an oven. The curing temperature was increased from room temperature
to 120 1C at a rate of 5 1Cmin
1
. The resin was cured at this temperature
for 3 h and post-cured at 150 1C for 1 h. Four polymer samples containing
different ratios of TOPERMA to styrene were prepared. The weight ratios of
TOPERMA monomer to styrene were 80 : 20, 70 : 30, 67 : 33 and 60 : 40, there-
fore the TOPERMA/styrene polymers were designated TOPERMA80-ST20,
TOPERMA70-ST30, TOPERMA67-ST33, and TOPERMA60-ST40, respectively.
The DCPD-UPR-TO liquid resins were cured according to the following
procedure: they were blended with the initiator benzoyl peroxide (2 wt% of
Scheme 8.4
Ideal chemical structure of the COPERMA macromonomer.
