(Natural) polymers

(Natural) polymersApplicationCharacterizationCustomer publicationsGIWAXSMaterialOrientation analysisOtherSurface structure and patternsTechniqueThin films

Highly Ordered Semiconducting Polymer Arrays for Sensitive Photodetectors

Wei, Xiao; Gao, Hanfei; Feng, Jiangang; Pi, Yueyang; Zhang, Bo; Zhai, Yu; Wen, Wen; He, Mingqian; Matthews, James R.; Wang, Hongxiang; Li, Yang; Jiang, Shimei; Jiang, Lei; Wu, Yuchen

Semiconducting conjugated polymers possess attractive optoelectronic properties and low-cost solution processability and are inherently mechanically flexible. However, the device performance is susceptible to the fabrication methods because of the relatively weak intermolecular interaction of the polymers and their inherent conformational and energetic disorder. An efficient fabrication technique…
12 March 2021
(Natural) polymersApplicationCharacteristic dimensionCharacterizationCustomer publicationsGIWAXSMaterialRenewable energySurface structure and patternsTechniqueThin films

Large Crystalline Domains and an Enhanced Exciton Diffusion Length Enable Efficient Organic Solar Cells

Zhang, Yiwei; Sajjad, Muhammad T.; Blaszczyk, Oskar; Parnell, Andrew J.; Ruseckas, Arvydas; Serrano, Luis A.; Cooke, Graeme; Samuel, Ifor D. W.

We studied crystallinity and exciton harvesting in bulk heterojunctions of the semiconducting polymer PffBT4T-2OD and electron acceptor PC71BM that are used to make highly efficient organic solar cells. Grazing incidence wide-angle X-ray scattering shows that the size of crystalline domains of PffBT4T-2OD increases to ?18 nm in photovoltaic blends upon…
12 March 2021
(Natural) polymersApplicationCharacteristic dimensionCharacterizationCustomer publicationsGIWAXSMaterialOrientation analysisRenewable energySurface structure and patternsTechniqueThin films

Overcoming the energy loss in asymmetrical non-fullerene acceptor-based polymer solar cells by halogenation of polymer donors

Fan, Qunping; Liu, Tao; Gao, Wei; Xiao, Yiqun; Wu, Jingnan; Su, Wenyan; Guo, Xia; Lu, Xinhui; Yang, Chuluo; Yan, He; Zhang, Maojie; Li, Yongfang

To achieve efficient polymer solar cells (PSCs), it is important to overcome the energy loss (Eloss) from the optical bandgap to the open-circuit voltage (Voc) of the device by properly matching donor/acceptor (D/A) photovoltaic materials. Here, we develop efficient PSCs based on the absorption complementary pairs of halogenated polymer donors…
12 March 2021
(Natural) polymersApplicationCharacterizationCustomer publicationsMaterialParticle interactionsPhase analysisPolymer researchSAXSSelf-assembled materialSizeTechnique

Order–Order Phase Transitions Induced by Supercritical Carbon Dioxide in Triblock Copolymer Thin Films

Abate, Anabella A.; Vu, Giang Thi; Piqueras, Cristian M.; del Barrio, María Cecilia; Gómez, Leopoldo R.; Catalini, Gabriel; Schmid, Friederike; Vega, Daniel A.

We study the influence of supercritical carbon dioxide (scCO2) on the phase behavior of a cylinder-forming polystyrene-block-polybutadiene-b-polystyrene triblock copolymer thin film. Solvent annealing with scCO2 can produce patterns with long-range order but these structures become unstable for thin films with small thicknesses. These results are in good agreement with self-consistent…
12 March 2021
(Natural) polymersApplicationCharacteristic dimensionCharacterizationCustomer publicationsMaterialPolymer researchSAXSSelf-assembled materialTechnique

CO2-Triggered and temperature-switchable crystallization-driven self-assembly of a semicrystalline block copolymer in aqueous medium

Zhu, Rui; Luo, Xinjie; Feng, Yujun; Billon, Laurent

The synthesis of a semicrystalline block copolymer comprising a hydrophilic poly(acrylic acid) (PAA) pure block and an amphiphilic poly(acrylic acid)-r-poly(octadecyl acrylate) (PAA-r-PODA) random block by nitroxide-mediated polymerization (NMP) is reported. The aggregation behavior of the copolymer in aqueous medium was studied by using a MicroCal VP differential scanning calorimeter (VP-DSC)…
12 March 2021
(Natural) polymersApplicationCharacterizationCrystalline fractionCustomer publicationsMaterialPhase analysisPolymer researchSAXSTechniqueTemperatureWAXS

Determination of the Critical Size of Secondary Nuclei on the Lateral Growth Front of Lamellar Polymer Crystals

Zhang, Shujing; Han, Jiarui; Gao, Yang; Guo, Baohua; Reiter, Günter; Xu, Jun

Nucleation is the rate-limiting first step of crystallization. The energy barrier related to form the critical nucleus predominantly affects the nucleation rate. Determination of the size of the critical nucleus is a key for understanding the mechanism of nucleation and allows testing theories. However, it has been a great challenge…
12 March 2021
(Natural) polymersApplicationCharacteristic dimensionCharacterizationCrystalline fractionCustomer publicationsGISAXSGIWAXSMaterialRenewable energySurface structure and patternsTechniqueThin films

Revisiting the Role of Graphene Quantum Dots in Ternary Organic Solar Cells: Insights into the Nanostructure Reconstruction and Effective Förster Resonance Energy Transfer

Sung, Sae Jin; Kim, Jae Ho; Gihm, Se Hoon; Park, Jisoo; Cho, Young Shik; Yang, Seung Jae; Park, Chong Rae

Recent studies have introduced the graphene quantum dot (GQD) as a third material for the bulk-heterojunction polymer:fullerene solar cell (PSC) to improve light conversion efficiency. Although exciton generation/dissociation and carrier transport in the GQD-incorporated light-absorbing layer are strongly influenced by the ternary component, detailed analysis on the role of GQD…
12 March 2021
(Hydro)gels(Natural) polymersApplicationCharacterizationCustomer publicationsMaterialParticle interactionsPolymer researchSAXSShapeSizeTechnique

Mechanical Properties and Failure Behavior of Physically Assembled Triblock Copolymer Gels with Varying Midblock Length

Mishra, Satish; Prado, Rosa M. Badani; Zhang, Song; Lacy, Thomas E.; Gu, Xiaodan; Kundu, Santanu

Mechanical properties including the failure behavior of physically assembled gels or physical gels are governed by their network structure. To investigate such behavior, we consider a physical gel system consisting of poly(styrene)-poly(isoprene)-poly(styrene) in mineral oil. In these gels, the endblock (PS) molecular weights are not significantly different, whereas, the midblock…
12 March 2021
(Natural) polymersApplicationCharacteristic dimensionCharacterizationCustomer publicationsMaterialNanoparticles & colloidsOrientation analysisParticlesSAXSTechnique

Polymer-Induced Modification of Cellulose Nanocrystal Assemblies in Aqueous Suspensions

Cohen, Neta; Ochbaum, Guy; Levi-Kalisman, Yael; Bitton, Ronit; Yerushalmi-Rozen, Rachel

The effect of adsorbing, nonionic polymers on the phase behavior of cellulose nanocrystals (CNCs) is of interest for design and preparation of functional hybrids. CNC assembly into a chiral nematic phase (N*) was investigated in the presence of highly hydrated poly(vinyl alcohol) (HPVA), low hydrated PVA (LPVA), and poly(vinylpyrrolidone) (PVP).…
12 March 2021