Nonlinear Optical Polyimides Research Articles

Synthesis and Properties of Novel Nonlinear Optical Polyimide Containing Nitrophenylazoresorcinoxy Group

New Y-type polyimide (4) containing nitrophenylazoresorcinoxy groups as NLO chromophores, which are components of the polymer backbone, was prepared and characterized. Polyimide 4 is soluble in common organic solvents such as N,N-dimethylformamide and dimethylsulfoxide. It shows a thermal stability up to 290°C in thermogravimetric analysis with glass-transition temperature (Tg) obtained from differential scanning calorimetry near 128°C. The second harmonic generation (SHG) coefficient (d 33) of poled polymer film at the 1064 nm fundamental wavelength is around 5.46 × 10−9 esu. The dipole alignment exhibits a thermal stability up to T g, and there is no SHG decay below 130°C due to the partial main-chain character of polymer structure, which is acceptable for NLO device applications.

Synthesis and Characterization of New Disperse-Red Functionalized Polyimide for Use as Nonlinear Optical Material

A new thermally-stable second-order nonlinear optical polyimide with side-chain second-order nonlinear optical (NLO) chromophore was synthesized. First a diamine functionalized azo chromophore (9) was synthesized and then polymerized by reaction with 4,4′-hexafluro isopropylidene-diphthalic anhydride. The synthesized polymer had a glass transition temperature of 215°C. The corona poling process of the NLO-substituted polyimide was also studied in detail by measuring the second harmonic generation (SHG) from the polymer films. The second harmonic measurement indicate long-term stability of the dipole orientation (>500 h at 150°C) for this polyimide.

Synthesis and characterization of nonlinear optical side-chain polyimides containing the thiadiazole chromophores

Thermally stable second-order nonlinear optical (NLO) polyimides were synthesized using a standard condensation polymerization technique. The polyimides were prepared from 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) and pyromellitic dianhydride (PMDA) with two aromatic azo- and diazo-diamine derivatives as the NLO chromophores. The resulting polyimides were characterized by FTIR, 1H-NMR, UV-vis spectroscopies, differential scanning calorimetry, thermogravimetric analysis, and gel permeation chromatography. The weight-average molecular weights of polyimides determined by gel permeation chromatography (GPC) were in the range of 32,100 to 39,300 (Mw/Mn = 1.58–1.74). All the polyimides exhibited an excellent solubility in many of the aprotic polar organic solvents, manifesting that these polyimides offer good processability. The glass transition temperature for the resulting polyimides was in the range of 152 to 194°C and most of them showed high thermal stability. Particularly, the polyimides containing diazo group and PMDA backbone showed an enhanced thermal stability and glass transition temperature. The second harmonic generation (SHG) coefficients (d33) of the poled polyimide films range from 43.71 to 80.49 pm/V at 532 nm. Further, it is noticed that there was no SHG decay below 180°C because of the partial main-chain character of the polyimide structure, which is acceptable for nonlinear optical device applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Electro-optic effect of a soluble nonlinear optical polyimide containing two different chromophores with different sizes in the side chain

A new soluble and thermally stable nonlinear optical (NLO) polyimide was synthesized by adding both tricyanopyrroline (TCP)- and tricyanofuran (TCF)-based NLO chromophores into the polymer backbone. The NLO polyimide (PI-II) bearing two different chromophores with different sizes has a glass transition temperature of 146 °C and exhibits good film forming properties. The electro-optic coefficient of the film was 84 pm/V at 1.3 μm under a poling field of 80V/μm, even though PI-II has an unusually high chromophore density of approximately 20 wt% of TCP chromophores and 23 wt% of TCF chromophores. Even with a overall chromophore loading of 43 wt%, no severe aggregation effect was observed for the sample that exhibited a relatively high EO coefficient. Open image in new window

Thermally stable hyperbranched nonlinear optical polyimides using an “A 2+B 3” approach

To obtain nonlinear optical (NLO) polyimides exhibiting excellent thermal stability and large electro-optical (EO) coefficients, we synthesized a series of novel hyperbranched polyimides from a tris(ether anhydride) [1,1,1-tris[4-(3,4-dicarboxyphenoxy)phenyl]ethane trianhydride (III)] and a difunctional chromophore [(2,4-diamino-4′-(4-nitrophenyldiazenyl)azobenzene) ( DNDA)], through ring-opening polyaddition at room temperature to form poly(amic acid)s (PAAs), followed by poling/curing process. The presence of the imide rings in the hyperbranched NLO polymers imparted them with excellent thermal stability. Moreover, their highly hyperbranched architectures resulted in site-isolation effects, which restricted the aggregation of the chromophore units. All of these hyperbranched polymers exhibited larger EO coefficients (14.6–17.2 pm V −1) and better temporal stability at 120 °C than those of linear NLO polymers. In addition, we also observed waveguide properties for hyperbranched NLO polymers (3.4–4.6 dB cm −1 at 1310 nm). Relative to the analogous linear NLO polyimide, the hyperbranched NLO polyimides exhibited superior temporal stability, larger EO coefficients, and lower optical losses.

Sequential self-repetitive reaction toward wholly aromatic polyimides with highly stable optical nonlinearity

A sequential self-repetitive reaction (SSRR) based on carbodiimide (CDI) chemistry was utilized for preparing a high-yield wholly aromatic polyimide. The polyimide was synthesized with 4,4′-methylene-diphenylisocyanate (MDI) and a di(acid-ester) compound which was derived from the ring-opening reaction of 3,3′,4,4′-oxydiphthalic dianhydride (ODPA) at room temperature by the addition of equimolar methanol. Poly-CDI was first synthesized from MDI. The di(acid-ester) compound was then reacted with poly-CDI to form poly(N-acylurea). After curing process, N-acylurea moiety was converted to di(ester-amide) structure viaSSRR and further subjected to a ring-closure reaction to form the wholly aromatic polyimide with a Tg of 247 °C. This approach was further taken to prepare thermally stable nonlinear optical (NLO) materials. Similarly a diimide-diacid containing chromophore was reacted with poly-CDI to obtain an intermediate, poly(N-acylurea). The poly(N-acylurea) with the ester side groups would exhibit excellent organosolubility, which enabled the fabrication of high quality optical thin films. After in situ poling and curing processes, N-acylurea moiety was converted to di(ester-amide) structure viaSSRR and further subjected to a ring-closure reaction to form the wholly aromatic NLO polyimide with an electro-optical coefficient, r33 of 25 pm/V (830 nm). Excellent temporal stability at elevated temperatures (200 °C) and a waveguide optical loss of 2.5 dB cm−1 at 1310 nm were also obtained.

Preparation, Morphological Characteristics and Electro-Optic Property of Polyimide and Hybrid

Nonlinear optical (NLO) polyimide and a series of polyimide/silica nanohybrids were synthesized from 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), NLO molecule 4-(4’- nitrophenyl-2-yl) phenyl-1,3-diamine, coupling agent and TEOS via sol-gel method. The TEOS content in the hybrids was varied from 0 to 22.5 wt%. The prepared hybrids were characterized by FT-IR, Differential Scanning Calorimetry (DSC), Thermogravimetric Analysis (TGA), Scanning Electron Microscopy (SEM) and Transmission Electron Microscope (TEM). The glass transition temperature (Tg) and the decomposition temperature (Td) at 5 % mass loss were in the range 232~365 °C and 335~475 °C, respectively. The results showed that the prepared materials had excellent thermal stabilities. The electro-optic coefficients (γ33) at 832 nm were in the range of 19-34 pm/V and the values remained well. The experimental results indicate that the prepared thin films have good candidate for electro-optical applications.

Thermally Stable Polyimide/Silica Hybrid: Synthesis, Characterization and Optical Nonlinearity

An intercalation nonlinear-optical (NLO) polyimide was synthesized based on the 3,3’, 4,4’- Bisphenyltetracarboxylic (BPDA) and [(6-nitrobenzothiazole-2-yl)diazenyl]phenyl-1,3- diamine (NBADA). Then, hybrid polymer was synthesized by the sol-gel technique. FT-IR spectroscopy and 29Si NMR were used to characterize the structure of the hybrid. The results revealed that Q3, Q4 and T3 are the major microstructure elements in forming a network structure. The surface morphology, particle size, crystallinity and the thermal stability of the hybrid were investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). DSC and TGA results showed that the glass transition temperature (Tg) and the decomposition temperature (Td) at 5% mass loss were 243, 359°C and 355, 456°C, respectively. These results showed that the hybrid material had excellent thermal stability than the pure polyimide. The electro-optic coefficients of nonlinear optical polyimide and hybrid were measured at the wavelength of 832 nm. The electro-optic coefficients were 22 and 19pm/V (poling voltage of 3.8KV, 210°C) and the values remained well (retained＞93% for more than 100h). The results suggest that the materials have potential applications for high performance optical device.

Preparation of novel T-type nonlinear optical polyimide with high thermal stability of second harmonic generation

2,4-Bis-(3,4-dicarboxyphenylcarboxyethoxy)-1-(2,2-dicyanovinyl)benzene dianhydride (4) was prepared and reacted with 1,4-phenylenediamine and 4,4′-oxydianiline to yield novel Y-type polyimides 5-6 containing 2,4-dioxybenzylidenemalononitrile groups as NLO-chromophores, which constitute parts of the polymer backbone. The resulting polyimides 5-6 are soluble in polar solvents such as dimethylsulfoxide and N,N-dimethylformamide. Polymers 5-6 showed a thermal stability up to 330°C in thermogravimetric analysis thermograms with T g values obtained from differential scanning calorimetry thermograms in the range 179–188°C. The second harmonic generation (SHG) coefficients (d 33) of poled polymer films at the 1064 nm fundamental wavelength were around 6.32 × 10−9 esu. The dipole alignment exhibited exceptionally high thermal stability even at 20°C higher than T g , there was no SHG decay below 200°C because of the partial main chain character of polymer structure, which is acceptable for nonlinear optical device ...

Nonlinear optical polyimides consisting of chromophore‐containing dendrons with site‐isolation effect

AbstractTo investigate the dendritic structure effects on the electro‐optical (EO) coefficients and thermal stability of the nonlinear optical (NLO) active materials, a bifunctional compound, IDD (4‐isocyanato‐4′(3,3‐dimethyl‐ 2,4‐dioxo‐acetidino)‐diphenylmethane) was used as a building block to synthesize a series of novel NLO chromophore‐containing dendritic structures including Generation 0.5 (G0.5) to Generation 3 (G3). The glass transition temperatures (Tg) of G1–G3 dendrons were in the range of 76–116°C, whereas only the G0.5 dendron exhibited a melting temperature (Tm), 98°C. Moreover, a series of NLO‐active guest–host systems ranging from polyimide‐G0.5 (PI‐G0.5) to polyimide‐G3 (PI‐G3) were prepared by blending 20 wt% chromophore‐containing dendron with a high Tg polyimide. EO coefficients ranged from 6.1 to 12.9 pm/V. The r33/dye content ratio increased with increasing generation of dendron‐containing polyimide samples. Particularly, the improvement in r33/dye content ratio of PI‐G2.5 sample tripled as compared to that of the guest–host sample with Disperse Red 1. Excellent temporal stability of PI‐G0.5 and PI‐G1.5 at 80°C was obtained. Moreover, waveguide properties for NLO polymers containing higher generation dendrons (3.1–3.6 dB/cm at 830 nm) were also obtained. Copyright © 2008 John Wiley & Sons, Ltd.

Synthesis and characterization of thermally stable second-order nonlinear optical side-chain polyimides containing thiazole and benzothiazole push–pull chromophores

Push–pull nonlinear optical (NLO) chromophores containing thiazole and benzothiazole acceptors were synthesized and characterized. Using these chromophores a series of second-order NLO polyimides were successfully prepared from 4,4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA), pyromellitic dianhydride (PMDA) and 3,3′4,4′-benzophenone tetracarboxylic dianhydride (BTDA) by a standard condensation polymerization technique. These polyimides exhibit high glass transition temperatures ranging from 160 to 188 °C. UV–vis spectrum of polyimide exhibited a slight blue shift and decreases in absorption due to birefringence. From the order parameters, it was found that chromophores were aligned effectively. Using in situ poling and temperature ramping technique, the optical temperatures for corona poling were obtained. It was found that the optimal temperatures of polyimides approach their glass transition temperatures. These polyimides demonstrate relatively large d 33 values range between 35.15 and 45.20 pm/V at 532 nm.

Preparation of Novel Y-Type Nonlinear Optical Polyimides with High Thermal Stability of Second Harmonic Generation

2,4-Bis-(3,4-dicarboxyphenylcarboxyethoxy)-1-(2,2-dicyanovinyl)benzene dianhydride (4) was prepared and reacted with 1,4-phenylenediamine and 4,4′-oxydianiline to yield novel Y-type polyimides 5-6 containing 2,4-dioxybenzylidenemalononitrile groups as NLO-chromophores, which constitute parts of the polymer backbone. The resulting polyimides 5-6 are soluble in polar solvents such as dimethylsulfoxide and N,N-dimethylformamide. Polymers 5-6 showed a thermal stability up to 330°C in thermogravimetric analysis thermograms with T g values obtained from differential scanning calorimetry thermograms in the range 179–188°C. The second harmonic generation (SHG) coefficients (d 33) of poled polymer films at the 1064 nm fundamental wavelength were around 6.32 × 10−9 esu. The dipole alignment exhibited exceptionally high thermal stability even at 20°C higher than T g , there was no SHG decay below 200°C because of the partial main chain character of polymer structure, which is acceptable for nonlinear optical device applications.

Synthesis and properties of novel Y‐type nonlinear optical polyimides with high thermal stability of second harmonic generation

Abstract2,4‐Bis‐(3,4‐dicarboxyphenylcarboxyethoxy)‐1‐(2,2‐dicyanovinyl)benzene dianhydride (4) was prepared and reacted with 4,4′‐oxydianiline, 4,4′‐diaminobenzanilide and 4,4′‐(hexafluoroisopropylidene)dianiline to yield novel Y‐type polyimides 5‐7 containing 2,4‐dioxybenzylidenemalononitrile groups as nonlinear optical (NLO) chromophores, which constitute parts of the polymer backbone. The resulting polyimides 5‐7 are soluble in polar solvents such as dimethylsulfoxide and N,N‐dimethylformamide. Polymers 5‐7 showed a thermal stability up to 330 °C in thermogravimetric analysis thermograms with Tg values obtained from differential scanning calorimetry thermograms in the range 179–194 °C. The second harmonic generation (SHG) coefficients (d33) of poled polymer films at the 1064 nm fundamental wavelength were around 5.56 × 10−9 esu. The dipole alignment exhibited exceptionally high thermal stability even at 20 °C higher than the glass‐transition temperature there was no SHG decay below 215 °C because of the partial main‐chain character of polymer structure, which is acceptable for NLO device applications. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3078–3087, 2008

Preparation and electro‐optic properties of novel Y‐type polyimides with highly enhanced thermal stability of second harmonic generation

AbstractBACKGROUND: In the development of nonlinear optical (NLO) polymers for electro‐optic device applications, stabilization of electrically induced dipole alignment is one of the important criteria. Polyimides for NLO applications have attracted attention because of their high Tg values and high thermal stability. In this work we designed and synthesized a new type of NLO polyimide, in which the pendant NLO chromophores are parts of the polymer backbone. These mid‐type NLO polymers are expected to have the merits of both main‐chain and side‐chain NLO polymers: stabilization of dipole alignment and good solubility.RESULTS: 3,4‐Bis‐(3,4‐dicarboxyphenylcarboxyethoxy)‐4′‐nitrostilbene dianhydride was prepared and reacted with the corresponding aromatic diamine to yield unprecedented Y‐type polyimides containing 3,4‐dioxynitrostilbenyl groups as NLO chromophores, which constituted parts of the polymer backbones. The resulting polyimides are soluble in polar solvents such as dimethylformamide and dimethylsulfoxide. These polymers showed a thermal stability up to 320 °C in thermogravimetric thermograms with Tg values obtained from differential scanning calorimetry thermograms in the range 143–164 °C. The second harmonic generation (SHG) coefficients (d33) of poled polymer films at the 1064 nm−1 fundamental wavelength were around 9.45 × 10−18 C.CONCLUSION: The dipole alignment exhibited exceptionally high thermal stability even at 30 °C higher than Tg. There was no SHG decay below 180–190 °C because of the partial main‐chain character of the polymer structure, which is acceptable for NLO device applications. Copyright © 2007 Society of Chemical Industry

Nonlinear optical polyimide/montmorillonite nanocomposites consisting of azobenzene dyes

A reactive organoclay was formed using trifunctional 1,1,1-tris[4-(4-amino-2-trifluoromethylphenoxy)phenyl] as a swelling agent for the silicate layers of montmorillonite. One of the functional groups of the swelling agents formed an ionic bond with the negatively charged silicates, whereas the remaining functional groups were available for further reaction with poly(amic acid) end capped with anhydride groups. Subsequently, the hydroxyl groups of the ensuing polyimide could be further reacted with isocyanate-containing dyes to form nonlinear optical polyimides with high T gs. X-ray diffraction and transmission electron microscopy revealed that the dispersion of silicate layers in the polyimide created an exfoliated structure as a result of using the trifunctional groups of the swelling agent. This particular structure of the nanocomposite resulted in enhanced thermal properties and excellent optical transparency. Using in situ contact poling, r 33 coefficients ranging from 4.6 to 7.6 pm/V were obtained for the organic/inorganic NLO materials; excellent temporal stability at 100 °C was obtained.

Synthesis and Optical Nonlinearity of Thermally Stable Polyimides Incorporated with Electro‐Optic Chromophore as Side Chain

AbstractWe prepared thermally durable nonlinear optical (NLO) polymers, based on a polyimide attached with a NLO chromophore as a side‐chain. The polyimide with two aromatic hydroxyls in the repeat unit was prepared by condensation polymerization between 2,2‐bis(3‐amino‐4‐hydroxyphenyl) hexafluoropropane and oxydiphthalic anhydride in DMAc, followed by imidization reaction. Mitsunobu coupling was carried out to incorporate the NLO chromophore into the polyimide backbone, to yield the side‐chain polymer with a loading level of the chromophore up to 65 wt%. The thermal characterization of the polymer showed that the NLO polyimide had Tg at 168 °C and was thermally stable up to 370 °C. The polymer solution was spin coated on the ITO glass to produce an optical quality film. The electro‐optic coefficient of the film was obtained using 1.55 µm laser source, giving 31 pm/V with an electrical poling field of 1 MV/cm. The temporal stability of the polymer was confirmed over 330 h at 85 °C under nitrogen condition.

A New Approach to Highly Electrooptically Active Materials Using Cross-Linkable, Hyperbranched Chromophore-Containing Oligomers as a Macromolecular Dopant

A new, practical approach to a variety of highly electrooptically active polymers for device development is described. It involves the use of a new thermally cross-linkable, hyperbranched oligomer containing nonlinear optical (NLO) chromophores as a macromolecular dopant in a common host polymer. A series of NLO polymeric blends were readily formulated and showed large and stable electrooptic (EO) coefficients (up to 65 pm/V). In comparison with previously studied linear NLO polyimides and guest-host polymers doped with molecular chromophores and even linear NLO analogous oligomers, this new approach offers clear advantages for device development in terms of improved poling efficiency, larger EO coefficients, good temporal stability, and versatile material formulation.

Cross-Linkable Zwitterionic Polyimides with High Electrooptic Coefficients at Telecommunication Wavelengths

A series of nonlinear optical (NLO) polyimides were prepared by grafting 4−16 wt % zwitterionic pyridinium tricyanoquinonedimethane chromophore with a large negative hyperpolarizability (β0 = −590 × 10-30 esu) onto the host polyimides through an ester bond formation. To enhance the temporal stability of the poled NLO polymers, a new thermally reactive group, i.e., 5-aminobenzocylcobutenone, was introduced into the NLO polymer systems to effect the cross-linking during the thermal poling process. The resulting NLO polyimides showed good solubility in polar aprotic solvents such as N,N-dimethylformamide and could form uniform films by casting or spin coating without any noticeable chromophore aggregation or phase separation as examined under an optical microscope. These NLO polyimides had glass transition temperatures in the range of 170−213 °C and were thermally stable up to 270 °C. The electrical resistivity of NLO polyimides was found to be on the order of 1015 Ω·cm at 80 °C and dependent on the applied voltages. As the temperature increased, the resistivity dropped monotonically to 2.4 × 1011 Ω·cm at 200 °C. With a 10 wt % chromophore loading (or a number density of 15 × 1019 cm-3) in the polymer, the electrooptic (EO) coefficient (r33 at 1550 nm) reached 45 pm/V. No substantial decrease in EO coefficients was observed after the test cell was kept in the dark at 85 °C under nitrogen after 1200 h nor when the test cell was irradiated with 1550 nm light (50 μW/∼4 mm2) for 10 h at ambient temperature in air.

Nonlinear optical polyimides with various substituents on chromophores: synthesis and glass transition temperature

Abstract Glass transition temperature ( T g ) of nonlinear optical polyimide was observed with a variation of substituents on chromophore side chain. Several alkyls and functional groups were synthetically introduced on both electron accepting and donating groups of the chromophores. The polymers were thermally characterized with a differential scanning calorimetric analysis (DSC). The glass transition occurred at a range of 160–230 °C according to introducing substituents. An ester group in the chromophore tends to lower T g in the corresponding polyimide compared to a nitrile or a sulfone. Flexible and bulky substituents led to decrease T g of the polymer. Electro-optic coefficients were measured to compare nonlinear optical performance of similar polymers with different T g .

A Side-Chain Dendronized Nonlinear Optical Polyimide with Large and Thermally Stable Electrooptic Activity

ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTA Side-Chain Dendronized Nonlinear Optical Polyimide with Large and Thermally Stable Electrooptic ActivityJingdong Luo, Marnie Haller, Hongxiang Li, Hong-Zhi Tang, Alex K.-Y. Jen, Kavitha Jakka, Chia-Hung Chou, and Ching-Fong ShuView Author Information Department of Material Science and Engineering, Box 352120, University of Washington, Seattle, Washington 98195 Department of Applied Chemistry, National Chiao Tung University, Hsin-Chu, Taiwan 30035, Republic of China Cite this: Macromolecules 2004, 37, 2, 248–250Publication Date (Web):December 23, 2003Publication History Received15 July 2003Revised4 December 2003Published online23 December 2003Published inissue 1 January 2004https://doi.org/10.1021/ma0350009Copyright © 2004 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views1008Altmetric-Citations94LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit Read OnlinePDF (84 KB) Get e-AlertsSupporting Info (1)»Supporting Information Supporting Information SUBJECTS:Aromatic compounds,Chromophores,Nonlinear optics,Polyimides,Polymers Get e-Alerts