The microelectronics industry is undergoing a transformation.
Today’s engineers are challenged to create lighter and thinner designs with high-performing components that meet the requirements of specific applications.
According to Functionalized Polynorbornene Dielectric Polymers: Adhesion and Mechanical Properties, “Polynorbornenes exhibit the key performance criteria for these demanding applications.” However, an un-functionalized polynorbornene exhibits poor adhesion to common substrate materials used in integrated circuits.
This is where functionalization comes in.
But first, what is a norbornene? What is a polynorbornene? Continue reading below to find out.
>>>Technology Tutorial: The Chemistry of Norbornene Monomers and Polymers
What is a norbornene?
A norbornene is a bridged cyclic hydrocarbon.
But, what does this have to do with polynorbornenes?The molecule (based on hydrogen and carbon) is manufactured via a Diels—Alder Reaction. The joining of a cyclohexene ring with a methylene bridge induces significant ring strain, resulting in a highly reactive double bond. Ring strain drives polymerization, the process in which monomer molecules form three-dimensional polymer chains.
Thanks to advances in research and development, scientists can copolymerize a wide variety of norbornenes with functional groups to tailor the polynorbornene compositions. With this, the foundation for cutting-edge components is made possible.
What is a polynorbornene?
Polynorbornene is a class of cyclic olefin polymers, which maintain the bicyclic ring structure of a norbornene without the use of non-norbornene based co-monomers.
This allows the polynorbornene backbone to remain rigid, effectively raising the high glass transition temperature. Unlike polyimides, which stiffen as they cure—simultaneously raising the glass transition temperature, polynorbornenes do not require high cure temperatures in order to achieve a high glass transition temperature.
Functionalization of Norbornene
Functionalized norbornenes contain a variety of reactive and non-reactive functional groups.
Possible substituents include:
- Acetate [-OC(O)R]
- Alcohol [-OH]
- Alkyl [-R]
- Amine [-CH2NH2]
- Anhydride [-RC(O)O(O)CR]
- Epoxide [-CH2CH(O)CH2 ]
- Ester [-CO2R]
- Ether [-OR]
- Ketone [-C(O)R]
- Phenyl [-Ar]
- Silyl Ether [-Si(OR)3]
- Vinyl [-CH=CH2]
From adjusting the modulus for stress compliance to modifying the elongation with controlled cross-linking, functionalization of norbornenes tunes the resulting polynorbornene for use in many different applications.
From surface energy to transparency, Promerus’ core technology provides the ability to incorporate functional groups into polynorbornenes. We encourage you to download our Materials Guide to see what Promerus can do for you.