Chemistry Reference
In-Depth Information
the resin) for 20 min and then with the promoter N,N-dimethylaniline
(0.2 wt% of the resin) for 2 min, poured into molds, cured at room
temperature for 24 h, and post-cured at 60 1C for 3 h.
The UPR/COPERMA resins were cured following a procedure similar to
that of the DCPD-UPR-TO resins: they were blended with the initiator ben-
zoyl peroxide (2 wt% of the resin) for 20 min and then with the promoter
N,N-dimethylaniline (0.2 wt% of the resin) for 2 min, poured into molds,
cured at room temperature for 3 h and at 60 1C for 3 h, at finally post-cured
at 80 1C for 1 h. The pure COPERMA resin with 35 wt% styrene was also
cured by this procedure. However, only semi-rigid COPERMA resin materials
were obtained under these curing conditions.
8.2.5 Characterization
8.2.5.1 Acid Value
The A
v
values of the oil-based UE macromonomers or UPEs were determined
according to GB/T 2895-1982. Typically, about 0.5 g of the product was
introduced into 30 mL of a toluene-ethanol (50 : 50 v/v) solution. Using
phenolphthalein as the indicator, the solution was titrated with a KOH/
ethanol solution, with an accurate concentration determined using a po-
tassium acid phthalate standard substance. The acid value was calculated
as:
15
A
v
ΒΌ
56
DV
C
KOH
1000
Dm
(1)
where DV, C
KOH
, and Dm denote the consumed volume and initial concen-
tration of the KOH solution, and the product weight, respectively.
8.2.5.2 Viscosity
The V
s
measurements of the oil-based resins diluted with styrene were
performed on a NDJ-8S rotational viscometer (Shanghai Changji Dizhi
Instrument Corporation, China).
8.2.5.3 Fourier-transform Infrared Spectroscopy
The FT-IR spectra were recorded on a Nicolet iS10 IR spectrometer (Thermo-
Fisher Corporation, USA).
8.2.5.4 Nuclear Magnetic Resonance
The
1
H-NMR spectra were recorded on a Bruker DRX-300 Advance NMR
spectrometer (Bruker Corporation, Germany).
