(1) Properties:

* copolymer of cationic monomer& acrylamide

* For carbonate reservoir( Acid/rock reaction)

* Viscosifying effectively to 20%HCL & 25%HCL.

* Good temperature & shear resistance, can be used in acid system of 180℃ reservoir.

(2) Characteristics:

--Good rheological & thermal stability

A: 0.8%DC-4099+20%HCL gel system is for 140-160℃reservoir. Viscosity can reach to 40-60mPa.s under 25℃/170 s-1condition, 30-35mPa.s under 90℃/170 s-1，and 20-30mPa.s under 120℃/170 s-1 condition.(as per chart 1)

B: 1.0%DC-4099+20%HCL gel system is for 160-180℃reservoir. Viscosity can reach to 50-70mPa.s under 25℃/170 s-1condition, 45-50 mPa.s under 120℃/170 s-1，and 20-30mPa.s under 160℃/170 s-1 condition.(as per chart 2)

Chart 1：0.8%DC-4099+20%HCL gel rheological graph

TEMP.℃

100

110

120

130

140

Viscosity

mPa.s

45.2

41.7

37.3

36.1

33.9

31.8

31.1

30.1

28.7

28.1

27.0

26.2

25.9

CHART 2: 1.0%DC-4099+20%HCL gel temp.-viscosity graph

--Good retarding performance

Test showed that the retarding rate of 0.8% DC-4099+20%HCL high-temp. gel is more than 90% compared with white acid

--Excellent fluid loss reducing property

DC-4099 high temperature gel is of perfect rheological function, effectively reduces the formation of fluid loss.

-- Superior performance and compatibility

It can mix with inhibitor, demulsifier, iron ion stabilizer, anti-swelling agent, soluble to water or acid.

(3) DC-4099 SPECIFICATIONS:

Items	Spec.
Appearance	White powder
Solid content, %	≥90%
Mesh	≤30
Solubility	Dispersed and dissolved in water and acid
Retarding rate	＞90%
Tackifying property	0.8% DC-4099+20%HCL, ≥40mPa.s under room temp./170s-1conditionand 20-30mPa.s in120℃； 1.0%FRK-V180+20%HCL, 20-25mPa.sunder 60/170s-1condition.
Reducing frictional resistance	25%-35% of water friction