STMMA Co-Polymer

Styrene is polymerized with methyl methacrylate (PMMA) in different proportions, and then immersed in a foaming agent during polymerization to make an expandable copolymer resin. The proportion of methyl methacrylate involved in the polymerization of STMMA is high, and the beads contain 63% carbon.

Methyl methacrylate has a molecular chain structure that is easy to decompose, and has no benzene ring, but very strong gasification capacity. After styrene is copolymerized with methyl methacrylate, the proportion of benzene rings in the copolymer molecular chain decreases. Besides, the rapid decomposition of methyl methacrylate can catalyze the decomposition of benzene rings. Therefore, the STMMA copolymer resin is more fully decomposed and highly gasified, and produces fewer solid residues during decomposition, thereby reducing carbon defects caused by casting.

Specifications

Product	Volatile Level (pentane w.t.)	Moisture	Beads Size Distribution Peak	Expanded Density Recommended	Min. Casting Wall Thickness
STMMA - #2	≥ 7.0%	≤ 0.50%	0.65–0.85	19–21 g/L	8.0 mm
STMMA - #3A	≥ 7.0%	≤ 0.50%	0.50–0.65	20–22 g/L	6.0 mm
STMMA - #3	≥ 7.0%	≤ 0.50%	0.36–0.50	21–23 g/L	5.5 mm
STMMA - #3s	≥ 7.0%	≤ 0.50%	0.33–0.35	23–26 g/L	4.5 mm

STMMA - #2

Volatile Level

≥ 7.0%

Moisture

≤ 0.50%

Beads Peak

0.65–0.85

Expanded Density

19–21 g/L

Min. Wall

8.0 mm

STMMA - #3A

Volatile Level

≥ 7.0%

Moisture

≤ 0.50%

Beads Peak

0.50–0.65

Expanded Density

20–22 g/L

Min. Wall

6.0 mm

STMMA - #3

Volatile Level

≥ 7.0%

Moisture

≤ 0.50%

Beads Peak

0.36–0.50

Expanded Density

21–23 g/L

Min. Wall

5.5 mm

STMMA - #3s

Volatile Level

≥ 7.0%

Moisture

≤ 0.50%

Beads Peak

0.33–0.35

Expanded Density

23–26 g/L

Min. Wall

4.5 mm

STMMA Co-Polymer

Specifications

Additional Images