New initiator for two-photon absorption induced polymerization with a microlaser at 1.06 μm

International audienceThe first part of this review presents the state of the art on two-photon absorbing molecules. Earlyworks concerned the optimization of dipolar push–pull molecules. Recently, the synthesis of linearand branched centrosymmetrical quadrupolar molecules led to higher nonlinearities, but still far from reachingthe fundamental limits of molecular two-photon cross-sections.The second part of this review summarizes our theoretical and experimental results on fluorene-basedoligomers, and branched oligomers (V-shape molecules and dendrimers). They are model molecules to investigatean alternative approach based on spatial assemblies of nonsubstituted π-electronsystems that are coupled by dipole–dipole interactions. In all geometries, two-photon absorptioncross-sections have superlinear dependencies that depend on coupling energies and oligomer sizes. Theseresults are well rationalized by an excitonic model based on N interactingthree-level systems. Analytical expressions for one-photon and two-photon energies and absorption strengthsare derived for linear oligomers. An accurate calculation of large exitonic systems is obtained by diagonalizingthe Hamiltonian operator on a reduced basis set

show abstract

“…For the near IR, Michler's ketone derivatives MK1 and MK2 were considered (Fig. 17) with σ TPA values up to 325 GM at 900 nm [102,103].…”

Section: Quadrupolar Moleculesmentioning

confidence: 99%

Excitonically Coupled Oligomers and Dendrimers for Two-Photon Absorption

Andraud¹,

Fortrie²,

Barsu³

et al. 2008

Advances in Polymer Science

View full text Add to dashboard Cite

show abstract

“…The TPP threshold has been previously identified as the local absorbed energy density below which the polymer will not form. [50] Using the same approach as Martineau et al, [50] an expression was derived for the dependence of lateral feature width, W, on the time-averaged incident power, <P(t)>, for a fixed exposure time of 1 ms (see Supporting Information)…”

Section: Point-by-point Exposurementioning

confidence: 99%

“…It is more desirable to determine <P(t)> min by fitting a plot of the feature width versus the average power with Equation 1 as shown in Figure 1b. [50] <P(t)> min and x 0 were determined in this fashion to be 9.1 mW and 393 nm, respectively. The absorbed energy density of the polymerization threshold, E th , for our system was then determined to be 3.07 nJ lm ±3 , using an equation derived by the same approach as Martineau et al [50] (see Supporting Information)…”

Section: Point-by-point Exposurementioning

confidence: 99%

See 1 more Smart Citation

Fabrication and Characterization of Two‐Photon Polymerized Features in Colloidal Crystals

Pruzinsky

2005

Adv Funct Materials

View full text Add to dashboard Cite

The fabrication and characterization of two‐photon polymerized features written within and outside of colloidal crystals is presented. Two‐photon polymerization (TPP) response diagrams are introduced and developed to map the polymerization and damage thresholds for features written via modulated beam rastering. The use of tris[4‐(7‐benzothiazol‐2‐yl‐9,9‐diethylfluoren‐2‐yl)phenyl]amine (AF‐350) as an initiator for TPP is demonstrated for the first time and TPP response diagrams illustrate the polymerization window. These diagrams also demonstrate that the polymerization behavior within and outside of colloidal crystals is similar and electron microscopy reveals nearly identical resolution. Fluorescence confocal microscopy further enables visualization of non‐self‐supporting, three‐dimensional TPP features within self‐assembled photonic crystals. Finally, microspot spectroscopy is collected from a two‐photon feature written within a colloidal crystal and this is compared with simulation.

show abstract

“…10 However, most of the reported chromophores exhibit high fluorescence yields as desirable for fluorescence imaging applications. 11,12 On the other hand, to be effective as a TPA initiator, low fluorescence quantum yields are preferred as this leads to a higher population of the triplet state (triplet quantum yield), which is usually the active state of the initiators producing radicals or ions for initiating the polymerization. 13 Thus, a large r TPA value combined with a high photoreactivity just like for normal one-photon initiators seems to be the goal to achieve.…”

mentioning

confidence: 99%

Synthesis and structure‐activity relationship of several aromatic ketone‐based two‐photon initiators

Siklos

Pucher

et al. 2011

J. Polym. Sci. A Polym. Chem.

View full text Add to dashboard Cite

Several novel aromatic ketone-based two-photon initiators containing triple bonds and dialkylamino groups were synthesized and the structure-activity relationships were evaluated. Branched alkyl chains were used at the terminal donor groups to improve the solubility in the multifunctional monomers. Because of the long conjugation length and good coplanarity, the evaluated initiators showed large two-photon cross section values, while their fluorescence lifetimes and quantum yields strongly depend on the solvent polarity. All novel initiators exhibited high activity in terms of two-photon-induced microfabrication. This is especially true for fluorenone-based derivatives, which displayed much broader processing windows than well-known highly active initiators from the literature and commercially available initiators. While the new photoinitiators gave high reactivity in two-photoninduced photopolymerization at concentration as low as 0.1% wt, these compounds are surprisingly stable under one photon condition and nearly no photo initiation activity was found in classical photo DSC experiment.

show abstract

New initiator for two-photon absorption induced polymerization with a microlaser at 1.06 μm

Cited by 37 publications

References 14 publications

Excitonically Coupled Oligomers and Dendrimers for Two-Photon Absorption

Excitonically Coupled Oligomers and Dendrimers for Two-Photon Absorption

Fabrication and Characterization of Two‐Photon Polymerized Features in Colloidal Crystals

Synthesis and structure‐activity relationship of several aromatic ketone‐based two‐photon initiators

Contact Info

Product

Resources

About