SYNTRAN® Polycarboxylates as Deflocculants for Ceramics

SYNTRAN® low- and medium molecular weight polycarboxylates as dispersion and deflocculation aids for the production of kaolin and alumina slurries in the ceramics manufacturing process. These polymeric dispersants are added during the grinding process to minimize the required energy input and grinding time.

SYNTRAN® polycarboxylates thus allow to yield casting slips (slurries) or high solids content (up to ca. 70%) with a low viscosity, good flowability and easy processability. The slurries are stabilized over an extended period of time and syneresis can be effectively avoided. Due to the reduction of water content less shrinkage in the mold, shorter drying times, and a higher green body strength can be achieved.

Typical use levels of SYNTRAN® polycarboxylates are 0.2 - 0.5 wt.% (as is) based on the amount of dry material. The best suited deflocculant and the minimum viscosity dosage depends on the nature and particle size of the clay particles and has to be determined experimentally.

INTERPOLYMER offers polycarboxylates in acid form as well as neutralized. Type and degree of neutralization may be varied upon request. Ammonium polycarboxylates are recommended for application in low sodium casting slips.

Deflocculants

Product

Typical Properties (Not Product Specifications)

SYNTRAN^®

Chemical Type

Total Solids

[wt.-%]

pH

Molecular Weight

GPC M_w

Brookfield Viscosity

[mPa.s] 25°C

Neutra-

lisation

8412-N *

AA / MA

43

8.1

5000

350

NaOH

8413-N *

AA / MA

40

8.0

N.A.

N.A.

NaOH

8520-A

AA / EA

40

7.5

4000

40-100

NH4OH

8520

AA / EA

50

2.0

4000

100-300

-

8220

AA

40

2.0

4000

35-65

-

8250

AA

40

2.0

18000

300-500

-

8251-A

AA

20

9.0

18000

20-50

NH4OH

* primary recommendation

AA: acrylic acid MA: maleic acid EA: ethyl acrylate

If products are preferred at a different pH or with a specific neutralizing agent, please contact INTERPOLYMER

SYNTRAN 8412-N

Grinding aid / deflocculating / dispersing agent in ceramic processing

SYNTRAN 8413-N

Equivalent to Acumer 9420 in performance
Grinding aid / deflocculating / dispersing agent in ceramic processing

SYNTRAN 8520-A

Ammonium salt solution of SYNTRAN 8520

SYNTRAN 8520

Highly suitable for fine ceramic compounds rich in alumina

SYNTRAN 8220

Also suitable for alumina

SYNTRAN 8250

Polyacrylic acid, of higher molecular weight than SYNTRAN 8220

SYNTRAN 8251-A

Ammonium salt solution. Of higher molecular weight than SYNTRAN 8520-A

Selection Guideline for the right Deflocculants

Type of Clay

Recommended Deflocculant

Body Clay of high plasticity

(e.g. bentonite, ball clay)

SYNTRAN 8412-N or 8413-N alone

or with STPP if required

90 : 10    (plastic : non plastic)

SYNTRAN 8412-N + STPP

or SYNTRAN 8413-N + STPP

70 : 30    (plastic : non plastic)

SYNTRAN 8413-N alone

or with STPP if required

50 : 50    (plastic : non plastic)

SYNTRAN 8412-N or 8413-N alone

or with SMS if required

10 : 90    (plastic : non plastic)

SYNTRAN 8412-N or 8413-N alone

China Clay (Kaolin) (low plasticity)

SYNTRAN 8412-N or 8413-N alone

or with NaOH

STPP: sodium tripolyphosphate

SMS: sodium metasilicate