Anti-shrink stability

Effects of MODIPER® S series

In case MODIPER® is not used as low profile additive, no low profile additive will satisfy all performance requirements for molding products.

Characteristics of Various Low Profile Additives

Low Profile Agent	Dispersal Stability	Anti-shrink stability	Surface Property	Mechanical Property	Coloration Characteristics	Transparency	Hot Water Resistant Property
PVAc	✔+	✔+	✔+	×	×	×	×
PMMA	✔-	✔-	✔-	✔-	✔-	✔-	✔-
PS	×	✔-	×	✔	✔	✔	✔
SBS	×	✔	×	✔-	✔	✔	✔
Cross-linked polystyrene	✔	× or ✔-	✔	✔-	✔+	✔ or ✔+	✔
MODIPER® S	✔	✔	✔	✔	✔- or ✔	✔-	✔
MODIPER® M	✔	✔-	✔	✔	✔+	✔+	✔

✔+：the most excellent　　✔：excellent　　✔-：rather good　　×：bad

Effect of MODIPER® S501

MODIPER® S501 has integration of PS segments and PVAc segments, so that MODIPER® S501 does not affect the mechanical properties and appearance of unsaturated polyester (UP).
On the other hand, in case the PS or PVAc are added simply as low profile additives, these additives can not work well because of poor compatibility in UP.

Comparison of MODIPER® S501 with PVAc/PS Simple Blend

Low Profile Additive	Before Curing	After Curing
MODIPER® S501
PVAc/PS Simple Blend

Effect of MODIPER® M202S

MODIPER® M202S has the functional groups that react with UP and does not cause interfacial delamination with UP, so that MODIPER® M202S does not affect transparency and hot water resistance of UP.
On the other hand, in case the cross-linked PS is added, it does affect the mechanical properties of UP due to interfacial delamination with UP.

Difference of Morphology between MODIPER® M and Cross-linked PS

Morphological Observation	Optical Microscope	SEM Photograph
MODIPER® M202S
Cross-linked PS