content_image/929655.jpg content_image/929648.jpg content_image/929657.jpg content_image/929654.jpg content_image/929656.jpg content_image/929647.jpg
(2) IR analysis: Measuring is carried out at room temperature with a Fourier-transform infrared spectrophotometer 1760X available from Perkin Elmer Co., Ltd. 

(3) GPC: A number average molecular weight is calculated from data measured by gel permeation chromatography (GPC) by using GPC HLC-8020 available from Toso Kabushiki Kaisha and colunms available from Shodex Co., Ltd. (one GPC KF-801, one GPC KF-802 and two GPC KF-806M were connected in series) and flowing tetrahy› drofuran (THF) as a solvent at a flowing rate of 1 ml/minute. 

Synthesis of Copolymer Comprising Cyclopentene and Tetrafluoroethylene 

A 100 ml autoclave was charged with 3.4 g of cyclopen› tene: 

<img src='content_image/929655.jpg'>

40 ml ofHCFC-141 band 0.3 g of bis( 4-tert-butylcyclohexyl) peroxydicarbonate (TCP), and the inside of a system was sufficiently replaced with nitrogen gas while cooling with dry ice/methanol solution. Then 10.0 g of tetrafluoroethylene (TFE) was introduced through a valve, followed by shaking for reaction at 40° C. for 18 hours. With the advance of the reaction, a gauge pressure was decreased from 0.78 MPaG (8.0 kgf/cm $^{2}$G) before the reaction to 0.75 MPaG (7.7 kgf/ cm $^{2}$G). 

After releasing the un-reacted monomer, the polymeriza- tion solution was removed, followed by re-precipitation with hexane to separate a copolymer. Until a constant weight was reached, vacuum drying was continued and 1.5 g of a copoly› mer was obtained. As a result of $^{1}$H-NMR and $^{19}$F-NMR analyses, the copolymer was one represented by the follow- ing formula. 

<img src='content_image/929648.jpg'>

The copolymer was one comprising TFE/cyclopentene in a percent by mole ratio of 50/50 according to an elementary analysis. According to GPC analysis, a number average molecular weight of the copolymer was 5,700. 

Reaction was carried out in the same manner as in Example 1 except that 3.5 g of 2,3-dihydrofuran: 

<img src='content_image/929657.jpg'>

was used instead of cyclopentene. 

Synthesis of Copolymer Comprising 2,3-dihydrofuran and Tetrafluoroethylene 

## Example 1 

## Example 2 

With the advance of the reaction, a gauge pressure was decreased from 0.78 MPaG (8.0 kgf/cm $^{2}$G) before the reac› tion to 0.75 MPaG (7.7 kgf/cm $^{2}$G). 

After releasing the un-reacted monomer, a polymer was separated in the same manner as in Example 1 and 2.1 g of a copolymer was obtained. As a result of $^{1}$H-NMR and $^{19}$F› NMR analyses, the copolymer was one represented by the following formula. 

<img src='content_image/929654.jpg'>

The copolymer was one comprising TFE/2,3-dihydrofuran in a percent by mole ratio of 50/50 according to an elementary analysis. According to GPC analysis, a number average molecular weight of the copolymer was 17,000. 

Synthesis of Copolymer Comprising Cyclooctene and Tetrafluoroethylene 

A 100 ml autoclave was charged with 2.8 g of cyclooctene: 

<img src='content_image/929656.jpg'>

40 ml ofHCFC-141 band 0.4 g of bis( 4-tert-butylcyclohexyl) peroxydicarbonate (TCP), and the inside of a system was sufficiently replaced with nitrogen gas while cooling with dry ice/methanol solution. Then 10.0 g of tetrafluoroethylene (TFE) was introduced through a valve, followed by shaking for reaction at 40° C. for 18 hours. With the advance of the reaction, a gauge pressure was decreased from 0.88 MPaG (9.0 kgf/cm $^{2}$G) before the reaction to 0.84 MPaG (8.6 kgf/ cm $^{2}$G). 

After releasing the un-reacted monomer, the polymeriza› tion solution was removed, followed by re-precipitation with methanol to separate a copolymer. Until a constant weight was reached, vacuum drying was continued and 2.7 g of a copolymer was obtained. As a result of $^{1 }$H-NMR analysis, the copolymer was one represented by the following formula. 

<img src='content_image/929647.jpg'>

The copolymer was one comprising TFE/cyclooctene in a percent by mole ratio of 52/48 according to an elementary 

## Example 3 

