Reactive mesogens particles (RMs) are polymerizable liquid crystal (LC) monomers with stiff cores and reactive terminal groups. The same approaches that are employed for low molecular mass LC can be used to align RMs. In the presence of photoinitiators and UV radiation, the end groups polymerize and form a film with other end groups.
As a result, the RM molecules’ orientation is “fixed,” while the film retains birefringence. This exceptional property makes them appealing as promising materials for light actuators like polarizers, color filters, retarders, and other devices. Reactive mesogens possess inherent properties of liquid crystals like self-assembly, anisotropic optical, and dielectric properties.
Nevertheless, they can be polymerized to solid materials while retaining their liquid crystalline alignments and anisotropic characteristics. The mesogenic property of RM materials, as well as polymerization, have led to a great variety of uses. Liquid Crystal Displays (LCDs) and Organic Light-Emitting Diode displays (OLEDs) both require functional films comprised of reactive mesogens particles. They significantly increase image quality in those displays.
Reactive Mesogens Chemicals-
RM257 CAS NO. 174063-87-7
R6M RM82 CAS NO .125248-71-7
RM23 CAS NO .83847-14-7
RM 105 CAS NO .82200-53-1
Let’s get into more information about RM257
RM257 is a nematic liquid crystal monomer (at 67–130 °C), that can be aligned by an electric field. This molecule has a 4:1 length ratio and stick structure. Its long axis is easy to bend and has some stiffness. Moreover, the molecular ends consist of polar or polarizable groups to keep the molecules in a well-ordered orientation.
The backflow effect refers to the joint influence of the tilt angle change and the flow effect in an LCD. In the applying voltage, vertical alignment liquid crystal display (VA-LCD), the backflow effect is shown as optical bounce (OB). The OB phenomenon significantly increases response time, limiting the use of VA-LCD in LC devices that demand quick response speed.
To eliminate the OB phenomenon during polymerization, little amount of bi-functional linear polymer monomer RM257 can be used to VA-LCD. As a result, a rapid reaction speed can be obtained. A modest amount of RM257 raises the saturation voltage while decreasing the transmittance of the bright state.
The VA-LCD with polymer monomer offers a simple manufacturing process, which is vital for its wide applications. The polymer monomer in the VA cell forms many vertical alignment fibers after polymerization. It has a certain anchoring effect on the LC molecules during the application of an electric field. Moreover, the horizontal flow of the LC molecules can also be blocked. The backflow impact is thus eliminated.
RM257 CAS NO. 174063-87-7