Photopolymerization of 1‐adamantyl acrylate pohotoinitiated by free radical photoinitiators

1‐Adamantyl acrylate was synthesized by reacting of 1‐adamantanol with acryloyl chloride in the presence of tertiary amine. The structure of monomer was characterized by FTIR and ¹H NMR spectroscopy. The influence of photoinitiator and monomer types on the photopolymerization kinetics of this monomer was investigated by real‐time infrared spectroscopy (RTIR). In the UV curing system, the introduction of 1‐adamantyl acrylate could significantly reduce the polymerization shrinkage. Thermogravimetric analysis of 1‐adamantyl acrylate indicated that 1‐adamantyl acrylate polymer has higher thermal stability than that of general commercial products. The results indicated that the synthesized monomer has good curing performance. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Novel polymerizable N‐aromatic maleimides as free radical initiators for photopolymerization

Four kinds of polymerizable N‐aromatic maleimides (MIs)—4‐[(4‐maleimido)phenoxy]benzophenone (MPBP), 4,4′‐bis[(4‐maleimido)phenoxy]benzophenone (BMPBP), 4‐maleimidobenzophenone (MBP), and 4,4′‐bismaleimidobenzophenone (BMBP)—were synthesized as free radical photoinitiators, by introducing directly N‐phenylmaleimide groups or maleimide groups into the molecule of benzophenone (BP). Compared with BP, their UV‐visible spectra have a significantly red‐shifted maximum absorption. The maximum absorption of MIs containing bifunctional maleimide groups is slightly larger than the corresponding monofunctional ones. Choosing an unsaturated tertiary amine N,N‐dimethylaminoethyl methacrylate (DMAEMA) as coinitiator, the photopolymerization of 1,6‐hexanediol diacrylate (HDDA), initiated by these four MIs, was studied through photo‐DSC. The results show that all the MIs are dramatically more efficient than BP. Among them, MPBP is the most efficient, in which the polymerization rate is almost three times as high as that of the BP system. Photoinitiators containing bifunctional maleimide groups, though having higher final conversion, are less efficient than the corresponding monofunctional ones. These polymerizable photoredox systems significantly reduced the migration of the active species, leading to their higher efficiency. Copyright © 2006 Society of Chemical Industry     

Selection of quaternary ammonium groups for optimizing properties of water‐soluble,photosensitive phenolic resins and study of their postcuring mechanism

This article deals with the selection of quaternary ammonium groups for synthesis of water‐soluble, photosensitive phenolic resins, containing acrylate and different quaternary ammonium salt groups (AQSPRs), via ring‐opening reactions of epoxy phenolic resin (EPR) with acrylic acid and with different tertiary amine‐protonic acid salts. Conversion of epoxy groups, solubility, photosensitive properties, and thermal decomposition of the different AQSPRs were compared. Modification of AQSPR with methanol solution of KOH to form phenolic resin containing both quaternary ammonium hydroxide groups and acrylate groups (AQHPR) was also studied. Characterization by IR spectrum, DSC, and thermal gravimetric analysis was carried out. The results showed that in the synthesis of AQSPRs containing different quaternary ammonium salt groups, the efficiency of ring‐opening reaction of epoxy phenolic resin with tertiary amine salt in terms of conversion of epoxy groups decreases in the following order: for the tertiary amine, N,N‐dimethyl benzylamine (DMBA) > triethylamine (TEA) > trimethylamine (TMA) > N,N‐dimethyl aniline (DMA) > triethanolamine (TENA) > tri(n‐butylamine) (TBA); for the protonic acid, HCl > HBr > HCOOH > HI > NaHSO₃ > Cl₃CCOOH > HClO₄ > HBF₄. All the AQSPRs except that from HClO₄ can be dissolved in water, methanol, DMF, or DMSO. The gel content formed during UV exposure decreases in the following order of acids used in forming quaternary ammonium salt groups: HCl > HCOOH > NaHSO₃ > Cl₃CCOOH; or decreases in the following order of tertiary amines or hydrohalic acids used in forming the quaternary ammonium groups: TMA. > TEA > DBMA; HCl > HBr > HI. During thermal decomposition of EPR with about half epoxy groups of EPR ring‐opened with tertiary amine salt at 160°C for 0.5 h, water‐insoluble product was formed. The insoluble content and the % decrease of epoxy groups or halide ions increase in the following order: TMA < TEA < DMBA; HCl < HBr < HI. The % decrease of epoxy groups for the insoluble residue is nearly equal to the % decrease of halide ions. A crosslinking reaction mechanism occurred in the thermal decomposition was thus proposed. During the modification of AQSPR with KOH, conversion of quaternary ammonium chloride groups can reach above 90%. The decomposition temperature of the quaternary ammonium groups was lowered from 204 to 120°C after modification of AQSPR with KOH. The photosensitive properties of the resin after modification became lower. It is better to react DMBA · HCl with EPR so as to obtain a product with higher conversion of epoxy groups, good water solubility, moderate photosensitivity, lower decomposition temperature, and better postcuring. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2914–2922, 2004     

Effect of N‐phenylmaleimide on a novel chemically bonded polymerizable photoinitiator comprising the structure of planar N‐phenylmaleimide and benzophenone for photopolymerization

A novel chemically bonded polymerizable photoinitiator 4‐[(4‐maleimido)phenoxy]benzophenone (MPBP) comprising the structure of planar N‐phenylmaleimide (NPMI) and benzophenone (BP), compared with the physical mixtures of NPMI/BP or NPMI/4‐hydroxybenzophenone, was investigated to disclose the mutual influence between NPMI and BP. A BP derivative, 4‐phenoxylbenzophenone, was selected as the model compound. Electron spin resonance spectra of such photoredox systems indicated MPBP and BP possess the same initiation mechanism. The large red‐shifted π–π* absorption of MPBP should be because of the phenoxyl group in MPBP but not the maleimide group. The photopolymerization of methyl methacrylate (MMA) and 1,6‐hexanediol diacrylate (HDDA) initiated by those systems, using the unsaturated tertiary amine N,N‐dimethylaminoethyl methacrylate (DMAEMA) as the coinitiator (H donor), was studied through dilatometry and photo‐differential scanning calorimetry. The results showed that MPBP was more efficient for the photopolymerization of MMA and HDDA than its physical mixture counterpart. The high efficiency of MPBP may be mainly because of the interaction between NPMI and BP group but not the phenoxyl group alone. A certain amount of NPMI can accelerate the photopolymerization when added to the formulations, but too much NPMI will eventually decrease the photoefficiency. Copyright © 2006 Society of Chemical Industry     

Synthesis of novel photochromic spiropyran dyes containing quaternary ammonium salt or cinnamoyl moiety and their properties as photoinitiators

Three novel spiropyran (SP) dyes containing quaternary ammonium salt or cinnamoyl moiety were synthesized and their photosensitive properties as photoinitiator were characterized by UV–vis spectroscopy. The intramolecular electron transfer of SP dyes containing quaternary ammonium salt was much faster and can initiate the photopolymerization under UV irradiation though the photochromic properties than those of SPs containing cinnamoyl group. A photoinitiation system containing SPs and the hexaarylbisimidazoles was studies, and the initiation properties were tested by monitoring the conversion rate of double‐bond at 810 and 1640 cm^?1 with ‐time infrared spectroscopy. It was found that the system containing our SP derivatives exhibited much higher initiating efficiency than ever reported SP dyes in the photopolymerization of 2‐phenoxyethylacrylate/N‐vinylcarbazole. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Toughening of cyanate ester resin by N‐phenylmaleimide–N‐(p‐hydroxy)phenyl‐maleimide–styrene terpolymers and their hybrid modifiers

N‐Phenylmaleimide–N‐(p‐hydroxy)phenylmaleimide–styrene terpolymer (HPMS), carrying reactive p‐hydroxyphenyl groups, was prepared and used to improve the toughness of cyanate ester resins. Hybrid modifiers composed of N‐phenylmaleimide–styrene copolymer (PMS) and HPMS were also examined for further improvement in toughness. Balanced properties of the modified resins were obtained by using the hybrid modifiers. The morphology of the modified resins depends on HPMS structure, molecular weight and content, and hybrid modifier compositions. The most effective modification of the cyanate ester resin was attained because of the co‐continuous phase structure of the modified resin. Inclusion of the modifier composed of 10 wt% PMS (M_w 136 000 g mol^?1) and 2.5 wt% HPMS (hydroxyphenyl unit 3 mol%, M_w 15 500 g mol^?1) led to 135% increase in the fracture toughness (K_IC) for the modified resin with a slight loss of flexural strength and retention of flexural modulus and glass transition temperature, compared with the values for the unmodified resin. Furthermore, the effect of the curing conditions on the mechanical and thermal properties of the modified resins was examined. The toughening mechanism is discussed in terms of the morphological and dynamic viscoelastic behaviour of the modified cyanate ester resin system. © 2001 Society of Chemical Industry     

Zwitterionic sulfobetaine‐modified non‐woven fabric for blood filtration

Blood filtration requires a high removal ratio of leukocytes and with simultaneous high recovery ratio of platelets and other beneficial components. Problems are often encountered with blood filter materials in terms of high platelet loss. Zwitterions such as phosphorylcholine, sulfobetaine and carboxybetaine show effective resistance against protein adsorption and platelet adhesion. The study reported was aimed at achieving surface modification of poly(butylene terephthalate) non‐woven fabric (PBTNF) using UV radiation‐induced graft copolymerization of a zwitterionic sulfobetaine, N‐(3‐sulfopropyl)‐N‐methacroyloxyethyl‐N,N‐dimethylammonium betaine (SMDB), in order to improve the wettability and platelet recovery ratio of the PBTNF. Attenuated total reflection Fourier transform infrared and X‐ray photoelectron spectroscopy results showed that SMDB was successfully grafted onto the PBTNF. Photoinitiator concentration, monomer concentration and UV irradiation time affected markedly the degree of grafting. Critical wetting surface tension, water wetting time and hemolysis tests showed an improvement in wettability and blood compatibility as a result of graft copolymerization of SMDB. A blood filter material composed of SMDB‐modified PBTNF reduced platelet adhesion and had higher platelet recovery compared to poly(acrylic acid)‐modified PBTNF. It was found that SMDB monomer was successfully grafted onto PBTNF using UV radiation. The degree of grafting of SMDB could be controlled by varying the photoinitiator concentration, monomer concentration and UV irradiation time. SMDB‐modified PBTNF showed significant improvement in wettability and blood compatibility. The zwitterionic structure of SMDB is resistant to platelet adhesion. The SMDB‐modified PBTNF could be a candidate for a blood filter material and in other medical applications. Copyright © 2010 Society of Chemical Industry     

Synthesis,Characterization and Properties of <Emphasis Type="Italic">N</Emphasis>-Alkyl-<Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>-di(2-hydroxyethyl) Amine Oxides

N‐Dodecyl‐N,N‐di(2‐hydroxyethyl) amine oxide (C₁₂DHEAO) and N‐stearyl‐N,N‐di(2‐hydroxyethyl) amine oxide (C₁₈DHEAO) were synthesized with N‐alkyl‐diethanolamine and hydrogen peroxide. Their chemical structures were confirmed using ¹H‐NMR spectra, mass spectral fragmentation and FTIR spectroscopic analysis. It was found that C₁₂DHEAO and C₁₈DHEAO reduced the surface tension of water to a minimum value of approximately 28.75 mN m^?1 at concentration of 2.48 × 10^?3 mol L^?1 and 32.45 mN m^?1 at concentration of 5.21 × 10^?5 mol L^?1, respectively. The minimum interfacial tension (IFT_min) and the dynamic interfacial tension (DIT) of oil–water system were measured. When C₁₈DHEAO concentration was in the range of 0.1–0.5%, the IFT_min between liquid paraffin and C₁₈DHEAO solutions all reached the ultra‐low interfacial tension. Furthermore, their foam properties were investigated by Ross‐Miles method, and the height of foam of C₁₂DHEAO was 183 mm. It was also found that they showed strong emulsifying power.     

Synthesis and ultraviolet‐curing behaviors of vinyl ether functionalized polyurethane oligomers

The vinyl ether functionalized oligomer is one of the most basic components of vinyl ether functionalized materials for cationic UV‐curable coatings. In this study, three types of vinyl ether functionalized polyurethane oligomers (i.e., polyether, polyester, and polydimethylsiloxane) were synthesized with diisocyanate, diol, and hydroxyethyl vinyl ether. These oligomers were characterized by IR, ¹H‐NMR, and ¹³C‐NMR spectroscopy. The effect of the raw material ratio on the oligomer, UV‐curing behaviors, and thermal properties of these oligomers were investigated. The UV‐curing behavior was analyzed by real‐time Fourier transform infrared spectroscopy. The vinyl ether terminated polyester urethane oligomer exhibited better UV curing, with a higher final conversion and maximum UV‐curing rates. In addition, the light intensity was enhanced for oligomers with better UV‐curing properties. Research on these vinyl ether functionalized oligomers is essential to the development and applications of cationic vinyl ethers systems. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40501.     

Synthesis and characterization of novel poly(γ‐benzyl‐L‐glutamate) derivatives tailored for the preparation of nanoparticles of pharmaceutical interest

Four poly(γ‐benzyl‐L ‐glutamate) (PBLG) derivatives bearing at one end specific groups were synthesized by ring‐opening polymerization of the corresponding γ‐benzyl‐L ‐glutamate N‐carboxyanhydride using different amine‐terminated initiators. These moieties were chosen to introduce, on demand, specific functionalities in nanoparticles of pharmaceutical interest. The PBLG and PBLG derivatives were characterized by ¹H NMR, viscosimetry, Fourier transform infrared spectroscopy and differential scanning calorimetry. Nanoparticles smaller than 100 nm in diameter could be easily prepared from these PBLG derivatives by slight modification of a known nanoprecipitation technique. Copyright © 2006 Society of Chemical Industry     

Water‐sorption and metal‐uptake behavior of pH‐responsive poly (N‐acryloyl‐N′‐methylpiperazine) gels

Hydrogels based on N‐acryloyl‐N′‐methylpiperazine (AcrNMP) swelled extensively in solutions of low pH due to the protonation of the tertiary amine. The water transport in the gels under an acidic condition was non‐Fickian and nearly Fickian in neutral pH with the collective diffusion coefficients determined as 2.08 × 10⁻⁷ and 5.00 × 10⁻⁷ cm⁻² s⁻¹, respectively. These gels demonstrated good metal‐uptake behavior with various divalent metal ions, in particular, copper and nickel, with the uptake capacity increased with increasing pH. The swelling ratio of the gel in the presence of metal ions decreased with increasing metal ion uptake. The results suggest that high metal ion uptake can lead to physical crosslinking arising from the interchain metal complex formation. The metal‐loaded gels could be stripped easily with 1M H₂SO₄ without any loss in their uptake capacity. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 268–273, 2001     

Synthesis and properties of ultraviolet/moisture dual‐curable polysiloxane acrylates

Ultraviolet (UV)/moisture dual‐curable polysiloxane acrylates (PSAs) were prepared from N,N‐bis[3‐(triethoxysilyl)propyl]amine (G402) and ethoxylated trimethylolpropane triacrylate (EB160) through Michael addition. The obtained prepolymers were characterized by ¹H‐NMR and FTIR. The rheological behavior of the prepolymers exhibited the properties of a Bingham fluid and the apparent viscosity was directly correlated with molecular weight. The photocuring kinetics of PSA were studied using photo‐DSC and all the polymerization conversions were high. With increasing content of tertiary amine in the prepolymer, the photocuring rate in air increased as well. The moisture‐curing kinetics of the prepolymers was studied using FTIR. It was found that the curing mechanism may be described as the transforming of Si O C into Si O Si structure, which was consistent with the theoretical expectation. DSC and TGA were used to characterize the glass‐transition temperatures and the thermomechanical stability of the prepolymers. Measurements of physical properties showed excellent gloss, impact strength, and high electric resistance for both UV‐ and moisture‐cured films, but poor adhesion for UV‐cured films and lower hardness for moisture‐cured films. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 846–853, 2005     

Synthesis and characteristics of photoactive‐hydrogenated rosin epoxy methacrylate for pressure sensitive adhesives

Hydrogenated rosin epoxy methacrylate (HREM), based on hydrogenated rosin and glycidyl methacrylate (GMA), was synthesized for use as an advanced tackifier in the UV‐crosslinking pressure sensitive adhesives (PSAs) system. The HREM, as a tackifier, contained UV‐curing sites; thus, allowed photopolymerization to occur by UV irradiation. This UV‐curable tackifier, HREM, can improve the curing rate and adhesion performance of UV‐crosslinking PSAs. The characteristics of HREM were analyzed by GPC and DSC and its synthetic mechanism studied using FTIR and ¹H NMR; the characteristic peaks of hydrogenated rosin and GMA vanished, but new peaks for HREM appeared. The PDI and the T_g by DSC were 1 and ?25.6°C, respectively. The photopolymerization of HREM was studied using photo‐DSC. Heat flow was observed during UV irradiation, and the curing rate and conversion both increased with rising photoinitiator content. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Effect of tertiary amines on yellowing of UV‐curable epoxide resins

The work reported demonstrates that the yellowness of UV‐curable epoxide resins can be improved by adding certain tertiary amines in appropriately determined amounts. According to the results of our experiments, 2.0 wt% benzoyl peroxide added to a resin effectively enhances the crosslinking density, and phenolic free radicals are produced during UV curing, which consequently induce yellowness via the reaction of oxygen and the free radicals. Imidazole (1‐amine) and tertiary amines, including 1,2‐dimethylimidazole (2‐amine), 2,4,6‐tris(dimethylaminomethyl)phenol (3‐amine), 1‐methylimidazole (4‐amine) and 2‐methylimidazole (5‐amine), were chosen to be added to resins, and their effects on UV conversion and yellowness were investigated. According to the experimental results, tertiary amines in the resin can provide a certain degree of improvement in yellowness index (ΔYI) and color parameter (ΔE*_ab) of the resin sample. Whatever the type of tertiary amine, it is found that the optimum content of amine in resin is 1.0 wt%. Also, among the studied amines, the 3‐amine exhibits the highest UV reactivity and the best efficiency for yellowness improvement with values of Δa*, Δb*, ΔYI and ΔE*_ab as low as ? 1.4, 6.23, 11.27 and 6.48, respectively. Copyright © 2007 Society of Chemical Industry     

Preparation and properties of fluorinated oligomer with tertiary amine structure in the UV curable coatings

A novel fluorinated oligomer with tertiary amine structure was synthesized by isophorone diisocyanate, 2‐hydroxyethyl acrylate, and fluorinated diol, which was prepared via Michael addition reaction between diethanolamine and dodecafluoroheptyl acrylate. The structure of fluorinated oligomer was confirmed by FTIR. The prepared fluorinated oligomer was added into the UV curable coatings, the influences of fluorinated oligomer on the cured degree and double bond conversion was analyzed by FTIR and gel content. The conversion ratio is increased when the fluorinated oligomer increased, which is due to the tertiary amine structure in the prepared product. The characteristics of UV cured films such as thermal properties, hydrophobicity, chemical resistance, mechanical properties, and hardness were characterized with the TGA, contact angle, and DMA. Results show that thermal stability, hydrophobicity, and chemical resistance are improved when fluorinated oligomer is introduced into the UV curable coatings. The DMA and hardness results indicated that the mechanical properties of UV cured films were improved and the flexibility decreased. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44387.     

Synthesis and photoinitiation properties of a novel quaternary ammonium tetraphenylborate salt

Quaternary ammonium salts are photobase generators. Recently, we prepared a novel quaternary ammonium tetraphenylborate salt bearing a 6‐methoxynaphthoylmethyl group. The structure of the products was confirmed by elemental analysis and ¹H‐NMR. Thermogravimetry showed its good thermostability. UV spectra and fluorescence emission spectra of the samples were studied. A mass spectrometry method for the analysis of the tertiary amine and other fragments produced by photolysis was established. Photolysis was found to produce both tertiary amine and free radicals. Therefore, the products of photolysis not only could cause thermal curing of epoxide but also could initiate the free‐radical polymerization of acrylate or methyl acrylate monomer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 399–405, 2006     

Novel biodegradable amphiphilic poly(ε‐caprolactone)/poly(N‐vinylpyrrolidone) blends via successive in situ polymerizations

In this study, biodegradable blends of poly(ε‐caprolactone) (PCL) and poly(N‐vinylpyrrolidone) (PVP) were prepared by a new strategy in the following steps: (1) free radical polymerization of N‐vinyl‐2‐pyrrolidone (NVP) in ε‐caprolactone (CL); (2) ring‐opening polymerization of ε‐caprolactone in the presence of PVP to obtain the target blends. The structure of the blends was confirmed by FTIR and ¹H NMR, and the molecular weight of PCL and PVP were determined by GPC. SEM study revealed that this polymerization method could decrease the disperse phase size and improve the interphase when compared with solution‐blending method. The phase inversion occurred when PVP content was 15–20 wt %. Subsequently, the PCL sphere dispersed in PVP matrix and its size decreased with the increase of PVP content. The contact angle results showed that PVP has a profound effect on hydrophilic properties of PCL/PVP blends. PCL/PVP blends are believed to be promising for drug delivery, cell therapy, and other biomedical applications. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Enhanced fracture toughness of epoxy resins with novel amine‐terminated poly(arylene ether sulfone)–carboxylic‐terminated butadiene‐acrylonitrile–poly(arylene ether sulfone) triblock copolymers

Amine‐terminated poly(arylene ether sulfone)–carboxylic‐terminated butadiene‐acrylonitrile–poly(arylene ether sulfone) (PES‐CTBN‐PES) triblock copolymers with controlled molecular weights of 15,000 (15K) or 20,000 (20K) g/mol were synthesized from amine‐terminated PES oligomer and commercial CTBN rubber (CTBN 1300x13). The copolymers were utilized to modify a diglycidyl ether of bisphenol A epoxy resin by varying the loading from 5 to 40 wt %. The epoxy resins were cured with 4,4′‐diaminodiphenylsulfone and subjected to tests for thermal properties, plane strain fracture toughness (K_IC), flexural properties, and solvent resistance measurements. The fracture surfaces were analyzed with SEM to elucidate the toughening mechanism. The properties of copolymer‐toughened epoxy resins were compared to those of samples modified by PES/CTBN blends, PES oligomer, or CTBN. The PES‐CTBN‐PES copolymer (20K) showed a K_IC of 2.33 MPa m^0.5 at 40 wt % loading while maintaining good flexural properties and chemical resistance. However, the epoxy resin modified with a CTBN/8K PES blend (2:1) exhibited lower K_IC (1.82 MPa m^0.5), lower flexural properties, and poorer thermal properties and solvent resistance compared to the 20K PES‐CTBN‐PES copolymer‐toughened samples. The high fracture toughness with the PES‐CTBN‐PES copolymer is believed to be due to the ductile fracture of the continuous PES‐rich phases, as well as the cavitation of the rubber‐rich phases. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1556–1565, 2002; DOI 10.1002/app.10390     

Design and Preparation of Tertiary Amine Modified Polyurethane Acrylate Oligomer with Co‐Initiation/Polymerization Bifunctions for Photo‐Curable Inkjet Printing of Textiles

In order to resolve the conflict issues existing in currently available polyurethane acrylate (PUA) oligomers for photo‐curable inkjet printing of textile, and to avoid the safety problems caused by the immigration of small molecule amine co‐initiator, a series of tertiary amine modified PUA oligomers are delicately designed and synthesized. The chemical structures of the synthesized PUA oligomers are confirmed by FTIR and ¹H‐NMR analyses. The optimized PUA oligomer/hydroxyethyl acrylate based polymerization system show a low viscosity, high storage stability and good compatibility with various functional segments. Furthermore, the modified PUA oligomer acts as both the photopolymerization constituent and the macromolecular co‐initiator assisting to achieve high photopolymerization rate and conversion rate, and avoiding the disadvantages caused by the migration of small amine co‐initiators. Benefitting from the semi‐IPN formed by this polymerization system with suitable crosslinking density and phase separation degree, a soft, strong and flexible cured film is obtained. The high photo‐reactivity with low viscosity of the polymerization system and the good flexibility with high strength of the resultant photo‐cured film ensures the applications of the modified PUA oligomer, and the printed fabrics achieve 4 grade of colorfastness with improved handle properties, as well as brilliant color and fine patterns.     

Synthesis and properties of new photosensitive and chiral poly(amide‐imide)s based on bicyclo[2,2,2]oct‐7‐ene‐2,3,5,6‐tetracarboxylic diimide and dibenzalacetone moieties in the main chain

Aromatic poly(amide‐imide)s (PAIs) are high‐performance materials with a good compromise between thermal stability and processability when compared with polyamides or polyimides of analogous structures. In addition, the incorporation of photosensitive functional groups and chiral segments into the polymer backbone can lead to interesting polymers for various applications. In this work, six new photosensitive and chiral PAIs were synthesized from the direct polycondensation reaction of novel N,N′‐(bicyclo[2,2,2]oct‐7‐ene‐tetracarboxylic)‐bis‐L ‐amino acids with 2,5‐bis(4‐aminobenzylidene)cyclopentanone as dibenzalacetone moiety using two different methods. The polymerization reactions produced a series of photosensitive and optically active PAIs in high yields and with good inherent viscosities. The resulting polymers were characterized using Fourier transform infrared and ¹H NMR spectroscopy, elemental analysis, inherent viscosity, specific rotation, solubility tests and UV‐visible spectroscopy. The thermal properties of the PAIs were investigated using thermogravimetric analysis. Due to the presence of the dibenzalacetone moiety in the polymer chain, the PAIs have photosensitive properties. Also, these PAIs are optically active and soluble in various organic solvents. These resulting new polymers have the potential to be used in column chromatography for the separation of enantiomeric mixtures. Copyright © 2009 Society of Chemical Industry