PsychoticSheepAnother photo from my training, this time captured during the analysis of a polymer sample under the light microscope β¨π¬
The material is based on a polycondensation reaction of 4,4Β΄-dihydroxybiphenyl with an aliphatic dicarboxylic acid chloride. Using an aqueous phase with sodium hydroxide and a phase transfer catalyst results in a polymer whose structure and properties strongly depend on the ordering of its molecular chains.
It becomes especially interesting when looking at the thermal and optical properties. In differential scanning calorimetry (DSC), the material shows two endothermic transitions. This means that the ordered structure is not lost all at once, but stepwise via a liquid crystalline phase into a fully isotropic state.
Under the polarizing microscope, this order becomes directly visible. The sample exhibits birefringence, meaning direction-dependent refraction of light. This only occurs when regions within the material are organized on a scale comparable to the wavelength of light. These structures are exactly what create the fascinating patterns and colors in the image.
In short, a small window into the world of liquid crystals, somewhere between ordered structure and thermally driven disorder.
I love these moments when chemistry is not only measurable, but also visible.
#chemistry #polymer #polymerchemistry #liquidcrystals #microscopy #polarizedlight #birefringence #materials #materialscience #lablife #science #research #stem #scicomm
The material is based on a polycondensation reaction of 4,4Β΄-dihydroxybiphenyl with an aliphatic dicarboxylic acid chloride. Using an aqueous phase with sodium hydroxide and a phase transfer catalyst results in a polymer whose structure and properties strongly depend on the ordering of its molecular chains.
It becomes especially interesting when looking at the thermal and optical properties. In differential scanning calorimetry (DSC), the material shows two endothermic transitions. This means that the ordered structure is not lost all at once, but stepwise via a liquid crystalline phase into a fully isotropic state.
Under the polarizing microscope, this order becomes directly visible. The sample exhibits birefringence, meaning direction-dependent refraction of light. This only occurs when regions within the material are organized on a scale comparable to the wavelength of light. These structures are exactly what create the fascinating patterns and colors in the image.
In short, a small window into the world of liquid crystals, somewhere between ordered structure and thermally driven disorder.
I love these moments when chemistry is not only measurable, but also visible.
#chemistry #polymer #polymerchemistry #liquidcrystals #microscopy #polarizedlight #birefringence #materials #materialscience #lablife #science #research #stem #scicomm
RDN
Lexmilian S. R. B. de Mello
EPFL
Lascivus Uncia
Nicole Sharp
John Faithfull ππͺπΊπ΄σ §σ ’σ ³σ £σ ΄σ Ώπ§‘βπ»βπΏ
Khurram Wadee β
