KURARITY™ – The transparent TPE
Author Robin Conrad
KURARITY™ is a series of acrylic block copolymers that are produced using Kuraray’s unique anionic living polymerization technology, which combines various (meth)acrylates into A-B or A-B-A type block copolymers. This controlled polymerization process enables KURARITY™ to remain exceptionally transparent and clean with minimal residual monomer or oligomer compared to conventional acrylic polymers that are produced using radical polymerization. KURARITY™ is also referred to as MAM (Methyl-methacrylate-Acrylate-Methyl-methacrylate), it consists of methyl methacrylate hard-blocks (PMMA-blocks) and an acrylic based soft-block (a PnBA-block or a P(nBA/2EHA)-block).
Due to its structure, KURARITY™ exhibits a variety of properties such as excellent transparency, weather resistance, self-adhesion and good compatibility with other polar materials. The acrylic-based block copolymer can be processed into a wide variety of applications, such as adhesives, coatings and sealants, 3D printing or light guides (especially in the mobility sector and home appliances). KURARITY™ can be used as an additive to modify polar plastics and is ready to use for injection and extrusion applications.
- Functional group / acid-free
- Excellent transparency
- Extremely low residual monomers or oligomers
- Less odor
- Excellent weatherability
- No hydrolysis degradation
- High-gloss, comparable with PMMA
- Excellent flexibility, without plasticizers
- Excellent injection / extrusion moldability
- Good compatibility with polar plastics
- Alternative to TPU
- High tack (without tackifier or plasticizer)
- Low hardness without plasticizer
- Residual-free adhesives
- No yellowing
- High adhesion to polar resin
- Adhesives, coatings, sealants
- Polymer modification
- Consumer goods
- Sporting goods & footwear
- 3D printing
Grades of KURARITY™
Kuraray developed two families of KURARITY™ called LA-series and LK-series. LA-series utilizes a poly (n-butyl acrylate) mid-block while the LK-series utilizes a poly (n-butyl acrylate/2-ethylhexyl acrylate) mid-block. The grades are differentiated by low PMMA content to high PMMA content, from low molecular weight to high molecular weight and by their applications.
All grades of KURARITY™ show similar low temperature properties which result from Tg of poly (n-butyl acrylate) mid-block or poly (n-butyl acrylate/2-ethylhexyl acrylate) mid-block and heat resistance from Tg of PMMA.
When used as a modifier for various types of polar resins (PC, ABS, PBT, PC/ABS, PMMA, PVC, PLA), inks, coatings, adhesives and other compounds, KURARITY™ imparts special properties such as improved flow-ability, impact resistance, softness and polarity. This effect is different compared to general core-shell type impact modifiers.
KURARITY™ – acrylic block copolymer
You can find more information about our products and applications in the R&D documentation.