NEW MEMBRANES FOR ENHANCED PURIFICATION OF NATURAL GAS AT THE WELLHEAD Chad J. Booth & Patrick E. Cassidy, Texas State University – San Marcos ACS-PRF Grant #46763-B7 The project goals are to examine a series of aliphatic polyimide films (synthesis and polymer structure shown below) and their subsequent TiO2 nanocomposites for potential use as a purification membrane for natural gas. During the first two years of the project we have completed the synthesis of the homologous aliphatic polyimide series, with and without the addition of TiO2 and have collected the thermal/mechanical data (shown below) on these materials. We continue to collect the gas permeation data for the native homologous series and will soon begin the collection of this data from the nanocomposites. More recently, we have started to synthesize a new series of polyimides which incorporate a rigid aliphatic diamine monomer. CF3
O
CF3
O
CF3
O
CF3
O H
DMAc
+
O
O
H2N
x
NH2
N
N
C
x n
H O
O
O
O X = 2 -10 & 12
Data for Aliphatic Polyimide Series with TiO2
550
550
500
500
450
450
400
Td Air Td Ar
350
Tg (DSC)
300
Tg (DMA)
250
Temp Deg C
Temp Deg C
Data for Aliphatic Polyimide Series
400
Td air
350
Td Ar Tg (DSC)
300
Tg (DMA)
250 200
200
150
150
100
100 2
4
6
8
10
# of Carbons in Aliphatic Spacer
12
2
4
6
8
10
# of Carbons in Aliphatic Spacer
12
