| CAS NO.56131-48-7 4-Cyanophenyl 4-ethylbenzoate | |
| Product Name | 4-Cyanophenyl 4-ethylbenzoate |
| Synonyms | 4-Ethylbenzoic acid-4′-cyanophenyl ester; 4-Ethylbenzoic acid-4′-cyanophenol ester; 4-Cyanophenyl-ethylbenzoate |
| CAS NO. | 56131-48-7 |
| Appearance | White solid |
| Purity | 95% min |
| MF | C16H13NO2 |
| MW | 251.28 |
| Storage | Preserve in a well-closed container and keep in cool, dry place, avoid light. |
| Package | In fluoride bottle/ Fluoride drums/iron drums/plastic drums/IBC Tank ,etc. |
| Shipment method | By Sea, Air, Courier door to door, etc. |
| Loading Port | China any port, Beijing, Shanghai, Hong Kong etc. |
| Application | 1. Nematic Liquid Crystal Mixtures for TN/STN Displays As a 4-cyanophenyl benzoate derivative, this compound contributes strong positive dielectric anisotropy to nematic liquid crystal mixtures through its highly polar cyano terminal group. The short ethyl chain on the benzoate ring maintains low rotational viscosity, enabling fast electro-optical response suitable for twisted nematic and supertwisted nematic display applications.
2. TFT-LCD Display Components The rigid biphenyl-type aromatic core connected through an ester linkage provides high optical anisotropy (birefringence), which is essential for achieving sufficient light modulation in TFT-LCD panels. The compound is incorporated into multi-component nematic mixtures to tune the overall electro-optical performance of the display. 3. Low-Viscosity LC Formulation Component The ethyl substituent is the shortest alkyl chain commonly used in the 4-cyanophenyl benzoate series, resulting in lower rotational viscosity compared to propyl, butyl, or longer alkyl homologs. This property makes the compound valuable in formulating LC mixtures that require fast switching speeds, such as those used in video-rate display applications. 4. Optical Anisotropy Tuning In multi-component liquid crystal formulations, this compound is used to adjust the birefringence (Δn) and dielectric anisotropy (Δε) of the mixture. The balance between the rigid aromatic core and the flexible ethyl tail provides moderate clearing point while ensuring reliable low-temperature operation. 5. Intermediate for Extended Mesogen Structures As a well-established phenyl benzoate ester, this compound serves as a building block in the formulation of complex liquid crystal mixtures. Its predictable mesomorphic behavior and compatibility with other common LC components make it suitable for custom display formulations requiring specific electro-optical characteristics. |
| Contact | Contact person: James Zhang
Email: james.zhang@dakenchem.com |
Frequently Asked Questions
Q1: What is CAS NO.56131-48-7 and what is its chemical structure?
CAS NO.56131-48-7, or 4-Cyanophenyl 4-ethylbenzoate, is a phenyl benzoate ester with molecular formula C16H13NO2 and molecular weight 251.28 g/mol. The molecule consists of two aromatic rings connected through an ester linkage: one ring bears a cyano (-CN) group at the para position, and the other carries a short ethyl (-C2H5) alkyl chain. This structure gives it rod-like (calamitic) molecular geometry typical of liquid crystal materials.
Q2: What type of liquid crystal phase does this compound form?
This compound is a thermotropic calamitic liquid crystal that exhibits nematic phase behavior. The rigid aromatic core promotes parallel molecular alignment, while the polar cyano group provides strong intermolecular dipole interactions necessary for nematic phase stability. The short ethyl chain prevents formation of more ordered smectic (layered) phases that longer alkyl chains would favor.
Q3: What role does the cyano group play in this compound?
The cyano (-CN) terminal group has a large dipole moment aligned along the long molecular axis. This contributes strong positive dielectric anisotropy (Δε > 0) to liquid crystal mixtures, meaning the molecules prefer to align parallel to an applied electric field. This property is essential for enabling low-voltage electro-optical switching in display devices.
Q4: How does the ethyl chain length affect the properties compared to longer alkyl homologs?
The ethyl chain is the shortest alkyl group commonly used in the 4-cyanophenyl benzoate series. Compared to propyl, butyl, or longer chain homologs, the ethyl derivative has lower rotational viscosity, resulting in faster response times. However, shorter chains generally provide narrower nematic temperature ranges and lower clearing points compared to longer chain variants.
Q5: What display technologies use this type of compound?
4-Cyanophenyl benzoate derivatives like this compound are used as components in nematic liquid crystal mixtures for: twisted nematic (TN) displays; supertwisted nematic (STN) displays; and as tuning components in TFT-LCD and IPS-mode formulations. The strong positive dielectric anisotropy from the cyano group is particularly valued in TN and STN applications requiring low operating voltage.
Application Cases
Application Case 1: TN Display Mixture Formulation
A display materials manufacturer incorporated this 4-cyanophenyl benzoate derivative into a multi-component nematic mixture for twisted nematic displays. The compound’s strong positive dielectric anisotropy from the cyano group enabled lower operating voltage in the final display panel, while the short ethyl chain contributed to maintaining fast response times suitable for standard video display refresh rates.
Application Case 2: STN Display Optimization
For a supertwisted nematic display application requiring steep electro-optical response curves, a formulation team used this compound to increase the overall dielectric anisotropy of their nematic mixture. The rigid aromatic core contributed to adequate birefringence for sufficient optical contrast, and the compound showed good compatibility with other standard nematic mixture components.
Application Case 3: Low-Viscosity LC Mixture for Fast Switching
A liquid crystal formulator working on a high-speed display application selected this ethyl-substituted phenyl benzoate over longer-chain homologs specifically for its lower rotational viscosity. The reduced viscosity compared to butyl or pentyl variants enabled faster molecular reorientation under applied electric fields, contributing to improved response time in the final device.
Application Case 4: Birefringence Tuning in Custom Mixture
A specialty LC mixture supplier used this compound as a birefringence tuning component in a custom formulation for an industrial display application. By adjusting the proportion of this high-birefringence component relative to lower-anisotropy base materials, the supplier was able to meet the customer’s specific optical performance requirements while maintaining acceptable viscosity and temperature range characteristics.
Application Case 5: Compatibility Testing for New Formulations
A display panel developer evaluating new nematic mixture formulations used this well-characterized 4-cyanophenyl benzoate as a reference component. Its predictable mesomorphic behavior and established compatibility with common LC materials made it suitable as a baseline compound for assessing the performance contribution of novel components being tested in the mixture.
