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Fluorescein and phenolphthalein derivatives have been synthesized and screened for their bioactivity via molecular docking, cytotoxicity and antioxidant studies. In molecular docking studies, the compounds 3d have exhibited better glide score and hydrogen bonding ability when docked with t-RNA Dimethylallyltransferase. Antioxidant capabilities were evaluated via DPPH and ABTS radical scavenging activity. In this screening, compound 3d exhibited better inhibition efficiency in the DPPH and ABTS methods. Cytotoxicity of the compounds was assessed by the cell sustainability assay against human cervical cancer cell line (HeLa). All the synthesized compounds exhibited cytotoxic effects against HeLa cells and compounds 3d displayed better activity (IC50) than the standard drug (doxorubicin).

Sol–gel-based phenolphthalein immobilized AuNPs (phph-AuNPs) of different shapes such as spherical, dendrites, and flower are observed by varying pHs 1–12. pH 1 induced the Au cages, and pH 2–6 revealed the different shapes of dendrites. Moreover, pH 7–8 assisted phph-AuNPs exhibited the spherical shape which transformed into truncated dendrites such as flowers at pH 9–11, and again spheres at pH 12. FTIR spectra exhibited the bonding vibration of AuNPs and phenols. pH 12 assisted phph-AuNPs are observed highly porous (79%) compared to pH 1 assisted phph-AuNPs (60%) porosity and low (1.1) refractive index. Furthermore, pH 1 assisted phph-AuNPs are found to possess RMS 11 nm and thickness 56 nm which increased up to 23 and 88 nm, respectively, by increasing the pH up to 12. The pKa ~9.4 of the pH 1–12 assisted phph dye is observed at 559 nm which increased up to 9.9 at 556 nm for pH 1–12 assisted phph-AuNPs, suggesting a wide range of sensitivity. Fast response time ~0.6 s is measured at pH 12 assisted phph-AuNPs. At acidic pH, higher photoluminescence (PL) intensity indicates a high charge carrier’s recombination. Experimental findings confirmed that pH has a great influence on the morphology of phph-AuNPs.

Electrospun polyimide (PI) ultrafine non-woven fibrous mats (UFMs) with good heat-fusibility via hot press procedure were successfully fabricated. For this purpose, two organo-soluble PI resins were prepared via a two-step chemical imidization procedure from two isomeric oxydiphthalic dianhydrides, including the asymmetrical ODPA (2,3,3′,4′-oxydiphthalic dianhydride, or aODPA) and symmetrical ODPA (4,4′-oxydiphthalic dianhydride, or ODPA) with an aromatic diamine containing phenolphthalein unit in the main chain, 3,3-bis[4-(4-aminophenoxy)phenyl]phthalide (BAPPT), respectively. The derived PI-1 (aODPA-BAPPT) and PI-2 (ODPA-BAPPT) resins showed high numerical average molecular weights (Mn) over 105 g/mol and were easily soluble in polar aprotic solvents, such as N-methyl-2-pyrrolidinone (NMP) and N, N-dimethylacetamide (DMAc). PI-1 and PI-2 UFMs were successfully prepared from the PI solutions in DMAc via the one-step electrospinning procedure. Different rotating speeds of 500–2500 round per minute (rpm) for the cylindrical collector were set to investigate the effects of the fiber morphologies on the properties of the PI UFMs. The derived PI UFMs showed good thermal stability with the glass transition temperatures (Tg) over 280 °C and 5 % weight loss temperatures (T5%) higher than 510 °C in nitrogen. The PI UFMs could be successfully heat-sealed via the hot-press temperature at 320 °C (about 40 °C higher than Tg) for 60s with the pressure of 0.5 MPa.

In this study, Plackett–Burman (P–B) experimental design combined with response surface methodology (RSM) of central composite design (CCD) was applied to study the removal of phenolphthalein (Php) from aqueous solution by aspartame functional magnetic dialdehyde starch nano-composite (APM-MDAS). This methodology enabled to identify the effects of the different factors studied and their interactions with a relative small number of experiments. By PBD, pH, sorbent dosage and contact time had a significant impact on Php removal. The maximum removal efficiency of phenolphthalein (95.41%) was achieved under the optimal conditions of pH, 10.68; sorbent dosage, 0.0015 (g mL−1); contact time, 118.13 s. The experimental results were in good agreement with the predicted values, indicating that the integrated P–B and CCD design is an effective approach for the statistical optimization of Php removal process. The kinetics of Php sorption fitted well with pseudo-second-order kinetic model and the isotherm data of compound could be well described by Langmuir model. The results showed that with convenient magnetic operation and synthesized by common industrialized raw materials, the APM-MDAS nano-composite is a novel, easy to prepare, environmentally friendly and effective adsorbent for the removal of phenolphthalein from aqueous solution. Additionally, the P–B design followed by the CCD method is an effective and powerful approach for the optimization of sorption process.

In this study, a new phenolphthalein derivative, FFIZNA, has been planned and successfully prepared in an uncomplicated way. The probe FFIZNA could selectively monitor Al3+ and Zn2+ among other relevant cations with diverse colors through a turn-on emission response in EtOH:HEPES (9/1;v/v) media owing to the chelation enhanced fluorescence (CHEF), prevention of ESIPT, -C=N- isomerization and PET of the probe FFIZNA. The interactions of Al3+ and Zn2+ with the probe FFIZNA were confirmed by emission spectroscopy, Job’s plot and 1H-NMR titration substantiated 1:2 reaction stoichiometry between FFIZNA and Al3+ and Zn2+. The time-response study displayed that the emission of FFIZNA with Al3+ and Zn2+, rapidly boosted and reached the stable value in less than 3.0 and 4.0 min, respectively. Therefore, the FFIZNA has successfully been utilized to the dual recognition of Al3+ and Zn2+ in solutions. Phenolphthalein conjugated schiff base as a dual emissive fluorogenic probe for the detection aluminum (III) and zinc (II) ions.

The modification of wool fabrics is significant in preparation of functional textiles. Sodium periodate oxidized β-cyclodextrin was grafted onto wool fabric through Schiff base reaction to obtain fabric with controlled release property. β-cyclodextrin was oxidized to aldehyde-β-cyclodextrin, and the results show that the inclusion constant and aldehyde content of aldehyde-β-cyclodextrin are varied with the reaction parameters such as molar ratio of reaction agents and the reaction temperature. The degree of oxidation was confirmed by ion chromatography. The drug loading test shows that the oxidized cyclodextrin still had inclusion ability towards phenolphthalein, while the inclusion constant was only 50 % of the original β-CD. The ATR-FTIR spectra proved the occurrence of grafting reaction between the aldehyde groups of aldehyde-β-cyclodextrin and the amino groups on wool fiber. The aldehyde-β-cyclodextrin grafted wool fabric show great washing durability even after 5 washing cycles. Compared with the aldehyde-β-cyclodextrin power, the inclusion ability of aldehyde-β-cyclodextrin fixed on the wool fiber decreased by 60 %.

Gas phase coagulation is a highly efficient method for fabricating physically crosslinked nanochitin-based hydrogels. In this study, a visible and tailorable strategy was developed using phenolphthalein and litmus indicator. The indicator was applied to stain partially deacetylated nanochitin (DEChNs), ensuring that the gelation process occurring during gas phase coagulation was able to be clearly visualized. A semi-gelatinized interface cross-sectional view was obtained, leading to the possibility to monitor and optimize the crosslinking process. Thereafter, a series of optimizations was performed to improve the nanochitin gelation process. Only 16.5 h was required for sufficient physical crosslinking when the molar ratio of ammonia to acetic acid was 3.45. In mixtures containing this proportion, the ammonia solution was completely reduced and the formation process was able to be controlled and improved. A higher concentration of nanochitin led to a slower cross-linking process, but increased the mechanical strength and produced a more uniform structure, which might be due to the formation of a more uniform network at an appropriate gelation rate. The optimization of the physical cross-linking process will improve our understanding of the mechanisms underlying the gas phase coagulation technique and the control of the properties of nanochitin hydrogels and their composites by altering the cross-linking conditions. The nanochitin gelation process was clearly visualized and optimized with substantially reduces the amount of ammonia solution and the precisely predicts and controls time, while it maintains a homogeneous and stable network structure, a higher specific surface and the same strong mechanical properties of the hydrogel.

Two semi-alicyclic polyimide (PI) films with light colors, good thermal stability, and enhanced flame retardancy were successfully developed from an aromatic diamine containing phenolphthalein unit, 3,3-bis[4-(4-aminophenoxy)phenyl]phthalide (BAPPT) and alicyclic dianhydrides, including 1,2,4,5-cyclohexanetetracarboxylic acid dianhydride (HPMDA) and 3,3',4,4'-bicyclohexanetetracarboxylic acid dianhydride (HBPDA). For this target, two organo-soluble PI resins, including PI-1 (HPMDA-BAPPT) and PI-2 (HBPDA-BAPPT) were first synthesized by a high-temperature polymerization route. The derived preimidized PI resins were soluble in N-methyl-2-pyrrolidinone (NMP), N,N-dimethylacetamide (DMAc), and other polar aprotic solvents. Corresponding PI films with pale-yellow appearances at the thickness of 25 μm were prepared by casting the PI solutions on glass substrates, followed by thermally baking at elevated temperatures up to 280 °C in nitrogen. The obtained PI films exhibited the cutoff wavelengths (λcut) lower than 300 nm, the optical transmittances as high as 84.5% at the wavelength of 450 nm, the yellow indices (b*) as low as 3.10, and the haze values as low as 3.71%. Both of the PI films exhibited good thermal stability with the 5% weight loss temperatures (T5%) higher than 480 °C in nitrogen, char yields higher than 40% at 700 °C, and glass transition temperatures (Tg) as high as 318.1 °C. In addition, the semi-alicyclic PI films showed acceptable high-temperature dimensional stability with the linear coefficients of thermal expansion (CTE) values of 52.3 × 10–6/K for PI-1 and 60.4 × 10–6/K for PI-2 in the temperature range of 50–200 °C, respectively. At last, the PI-1 film showed good flame retardancy with the limited oxygen index (LOI) of 32.8%, the flame retardancy class of UL94 VTM-0, and good smoke suppression properties.

Perpendicular cardo structural units were inserted into a polyurethane (PU) framework from the pH indicator (phenolphthalein (PP), phenol red (PR), or bromocresol green (BG)) sharing a triphenylmethyl group. The thermal transitions, mechanical properties, pH-sensitive color change, and low temperature flexibility of the PU modified with the cardo structural units were compared with those of the ordinary PU. Slight cross-linking between PU chains was performed because the insertion of the indicator moieties deteriorated the mechanical properties. The breaking tensile stress and shape recovery capability at 0 °C of the BG-PU series surpassed those of the PP-PU and PR-PU series. The inserted pH indicator moieties did not show the color change under different pH conditions because the isomerization under basic conditions was blocked. Among the three series of PUs, the BG-PU demonstrated the best low temperature flexibility compared with that of the PP-PU and PR-PU due to the functional groups on the phenyl rings of BG. Insertion of a cardo structural unit from the pH indicator reduced the molecular interaction between PU chains.

An effective approach is proposed to fabricate hybrid multilayer stealth composite composed of carbon fiber/bismaleimide composites containing carbon coated Fe (Fe@C)/phenolphthalein polyetherketone (PEK-C) nano-membranes as interlaminar electromagnetic absorbing agents. Dynamic mechanical analysis and interlaminar shear strength tests were carried out to evaluate mechanical properties. Special attention was paid to the permittivity, permeability and microwave absorbing properties. The results indicated that the radar-absorbing structural materials (RASs) showed a minimum reflection loss (RL) value of − 16.85 dB observed at 11.5 GHz at a thickness of 1.7 mm, with the values exceeding − 10 dB achieved in 9.7–16.7 GHz with increasing thicknesses. The measured RL values were in good agreement with the calculated ones. This strategy may be extended as a versatile approach to achieve high performance RASs, thereby promoting their engineering applications at low cost in aerospace industry.

Perforative silica microspheres (PSMs) were prepared by an emulsion method coupled with sol–gel technology and phase separation. Next, phenolphthalein-based poly(arylene ether sulfone)/PSM composites (PES-C/PSM) were fabricated. PSM was characterized by scanning electron microscopy (SEM) and the Brunauer–Emmett–Teller (BET) method. The as-synthesized PSM exhibited a spherical shape with an external diameter of 2–10 µm, surface area of 166.5 m2/g and pore volume of 1.35 cm3/g. SEM and energy-dispersive spectroscopy (energy-dispersive spectroscopy) were used to characterize the morphology and the composition of the composite, respectively. Both SEM and energy-dispersive spectroscopy results revealed that the PES-C polymer chains penetrated into the PSM pores. In addition, the effect of PSM weight content on the mechanical properties and thermal stability of the composites was characterized by tensile tests and thermal analysis, respectively. A 19% increase in tensile strength and a 29% increase in breaking elongation of PES-C were achieved by the addition of 0.50 wt% PSM. Moreover, the thermal oxidative stability of PES-C was remarkably improved with the incorporation of PSM. Compared with pristine PES-C, the final degradation temperature was enhanced by 42 °C at 1.0 wt% PSM loading. Our studies have indicated that PSM is a kind of promising reinforcement for improvement of tensile and thermal properties of engineering plastics.

Adulteration of herbal medicinal products with synthetic pharmaceuticals remains a serious problem. The purpose of this study is to develop a procedure for determination of some common synthetic adulterants in some herbal remedies available on the market, utilizing a reversed-phase high-performance liquid chromatography (HPLC) method with ultraviolet (UV) detection. Herbal medicines for weight loss and another for erectile dysfunction were tested for presence of conceivable adulterants. The weight loss products were discovered to be defiled with the effectively withdrawn drug sibutramine (SIB) and with phenolphthalein (PPH), which has been demonstrated to cause tumors. On the other hand, sildenafil (SLD), a medication contraindicated for patients with heart diseases (sometimes causing serious side-effects with respect to blood pressure), was found in the herbal product for erectile dysfunction. The mobile phase for quantification of sibutramine and phenolphthalein was acetonitrile–potassium hydrogen phosphate buffer (pH 3) adjusted using o-phosphoric acid (40/60 v/v) with detection at 223 nm. Meanwhile, the mobile phase for sildenafil was acetonitrile–potassium hydrogen phosphate buffer (pH 3.2) adjusted using o-phosphoric acid (50/50 v/v) with detection at 230 nm. Presence of the adulterants was confirmed using LC–photodiode array (PDA) and mass spectrometry.

The consumption of dietary supplements is increasing every year all over the world. In addition, the consumption has been accompanied by the increased frequency of adulteration of the products with synthetic pharmaceuticals. Analytical methods that allow testing the presence of synthetic drugs in dietary supplements are needed to detect such fraudulent practices. This paper describes the study of furosemide, hydrochlorothiazide, chlorthalidone and amiloride (diuretics), fluoxetine and paroxetine (antidepressants), and phenolphthalein (laxative) and amfepramone (anorexic) in dietary supplements marketed in Brazil for weight loss and physical fitness claims. A total of 113 products were acquired from websites and physical stores. The analytical method applied in this work involved the separation of the compounds by capillary zone electrophoresis in a working electrolyte consisting of 30% (v/v) methanol in a 20-mmol L−1 phosphate buffer (pH 9.2) and capacitively coupled contactless conductivity detection and UV detection simultaneously. The method was validated in accordance with the appropriate guideline of the Association of Analytical Communities (AOAC) and was successfully applied to the analysis of the samples of dietary supplements. Hydrochlorothiazide was present in 14 of the studied samples. One sample presented furosemide in addition to hydrochlorothiazide, both acting as diuretics.

Thermally stable acid catalyzed mesoporous titania (TiO2) nanomatrices are obtained by sol–gel method for fiber optic pH sensing. These synthesized nanoparticles are annealed at 300 °C, at two time intervals i.e., 1 h and 2 h, characterized with several analytical techniques such as FE-SEM/EDS, AFM, XRD, FTIR, TGA, and Brunauer–Emmett–Teller (BET) analysis. Microscopic analysis shows that synthesized nanoparticles have crack-free, dense and homogeneous surface with low surface roughness (4.4–5.9 nm). EDS mapping confirms the uniform distribution of Ti in all samples. XRD findings revealed the TiO2 anatase phase. BET analysis shows that the mesoporous synthesized TiO2 nanoparticles have surface areas 169 m2/g and average pore diameter 39.2 A. However, surface area is decreased to 113 and 102 m2/g and average pore diameter increased up to 62.36 and 68.18 A after 1 h and 2 h heat treatment, respectively. Furthermore, the sensing activity of phenolphthalein (phph) doped mesoporous TiO2 nanoparticles/matrix is found to be high at pH 12 without any leaching/cracking.

Nanocomposites obtained by in situ filling from amorphous poly(arylene ether ketones) based on 4,4´-difluorobenzophenone and 3,3-bis(4´-hydroxyphenyl)phthalide (phenolphthalein) with hydroxyl or benzophenone end groups were investigated. Metalalkoxysiloxanes, namely tris-(diethoxymethylsiloxy)iron, tetrakis-(diethoxymethylsiloxy)zirconium, and tetrakis- (diethoxymethylsiloxy)hafnium were used as precursors of the inorganic phase. It is shown that the morphology of the inorganic phase of nanocomposites can be varied from dispersed particles to a continuous network only by changing the type of the central metal atom of the metalalkoxysiloxane with the same organosilicon “framing”. The concentration of the precursor influences mainly the size of the filler particles. An application of tris-(diethoxymethylsiloxy)iron at a concentration of less than 14 wt.% makes it possible to obtain in situ filled polymers with a higher glass transition temperature than the ones obtained using tetrakis-(diethoxymethylsiloxy)zirconium or tetrakis-(diethoxymethylsiloxy)hafnium.

Acid dissociation constant is an important chemical characteristic of organic and inorganic compounds and it affects both chemical properties and biological activities of the molecules. Herein, a very simple, fast and cost-effective method based on microfluidic technology has been reported for colorimetric determination of acidity constants. The designed device works based on pH-metric titration of colorful indicators followed by colorimetric measurements by a smart phone mobile device or a flatbed scanner. So, it does not need sophisticated instrumentation and is accomplished in a very short time (about 1 min). All titration steps are transferred on a star-like designed µPAD device: (1) spotting 0.3 µL buffers of different pHs at the end of the channels (reaction zones), (2) spotting a 30 µL portion of the indicator on the center of µPAD followed by movement of indicator solution toward the reaction zone by capillary action of the paper. The measured color change of the indicators at the reaction zone is fitted to the Henderson–Hasselbalch equation, through which acidity constants are calculated. The performance of the device was evaluated by measuring acidity constant of 4 indicators including bromothymol blue, bromocresol green, bromocresol purple and phenolphthalein. A very close agreement was achieved between those measured by the suggested device here and the previously reported values. The reproducibility of this method was lower than 5% for relative standard deviation of three replicate measurements.

Phenolphthalein (PP series) or 4-tritylaniline (TA series) was used for grafting onto polyurethane (PU), and the effects of two grafted groups on the soft segment glass transition, tensile strength, recovery to original shape, and flexibility at freezing temperature were investigated. The soft segment melting of PP series and TA series was not significantly affected with increases in phenolphthalein or tritylaniline content. The soft segment glass transition temperature (T g ) of PP series clearly increased as the PP content increased, whereas TA series exhibited a little increase in T g with increases of TA. Solution viscosity, degree of cross-linking, shape recovery at 10 °C, and tensile strength of PP series clearly increased with increases in PP because of cross-linking in the grafted phenolphthalein, whereas TA series did not demonstrate the same degree of enhancement with increases in TA. In contrast to plain PU and TA series, PP series displayed outstanding flexibility below 0 °C. Therefore, compared to plain PU, the grafting of phenolphthalein clearly enhanced the tensile strength, flexibility under freezing, and recovery to original shape of the polymer.

In this paper, titanium dioxide (TiO2)/phenolphthalein-type polyimide (PPPI) composite was synthesized in situ polymerization, the diamino phenolphthalein type compound and dimethylacetamide as the matrix, and TiO2 as the filler. The mechanical property and thermal conductivity properties were used to characterize the properties of the obtained composite. A diamine monomer containing more benzene rings of phenolphthalein and an ether bond in its main chain were prepared, synthesized by a nucleophilic substitution reaction and a hydrazine hydrate reduction reaction. Polyimide composite had the same structure as that of a diamine monomer. And it was synthesized by solution imidization and heat imidization. The results showed that TiO2 improved the dispersibility, alignment and interfacial strength of the TiO2/PPPI composite. The mechanical property of polyimide composite was increased with the increasing TiO2 loading. And a suitable addition of TiO2 could enhance the mechanical properties of polyimide system. Compared to polyimide resin, the TiO2/PPPI composite had a higher thermal conductivity with the increasing of TiO2 content. All of these changes in properties were closely correlated with the TiO2/PPPI composite, which could form an interaction interface structure in the system.

This research aimed at investigating the effect of epoxy resin and flame retardant additives on oil palm trunk particleboard. The oil palm trunk was used as a raw material with epoxy resin as a binder, which was synthesized by a reaction of epichlorohydrin and phenolphthalein, while aluminium hydroxide and magnesium hydroxide were used as flame retardant additives to manufacture particleboards. Four different types of particleboards were produced, control board, board with 10% epoxy resin, board with 10% epoxy resin and 6% aluminium hydroxide and board with 10% epoxy resin and 6% magnesium hydroxide, based on a target density of $$0.80~\hbox {g}~\hbox {cm}^{-3}$$, at a temperature of $$180^{\circ }\hbox {C}$$, a pressure of 5 MPa and a pressing time of 20 min. The mechanical, physical, functional group, spectroscopic, morphological and elemental analysis properties were determined in comparison with control particleboard. Thermal degradation and flame retardant analyses were also carried out to analyse the thermal properties of particleboards. The results indicated that particleboard bonded with epoxy resin and flame retardant additives had improved mechanical, physical, thermal and flame retardant properties compared to control oil palm trunk particleboard. Overall results showed that epoxy resin as a binder and aluminium hydroxide and magnesium hydroxide as additives have the potential to be incorporated into the particleboard to improve flame retardant properties.

The whole-cell immobilization on chitosan matrix was evaluated. Bacillus sp., as producer of CGTase, was grown in solid-state and batch cultivation using three types of starches (cassava, potato and cornstarch). Biomass growth and substrate consumption were assessed by flow cytometry and modified phenol-sulfuric acid assays, respectively. Qualitative analysis of CGTase production was determined by colorless area formation on solid culture containing phenolphthalein. Scanning electron microscopy (SEM) analysis demonstrated that bacterial cells were immobilized on chitosan matrix efficiently. Free cells reached very high numbers during batch culture while immobilized cells maintained initial inoculum concentration. The maximum enzyme activity achieved by free cells was 58.15 U ml(-1) (36 h), 47.50 U ml(-1) (36 h) and 68.36 U ml(-1) (36 h) on cassava, potato and cornstarch, respectively. CGTase activities for immobilized cells were 82.15 U ml(-1) (18 h) on cassava, 79.17 U ml(-1) (12 h) on potato and 55.37 U ml(-1) (in 6 h and max 77.75 U ml(-1) in 36 h) on cornstarch. Application of immobilization technique increased CGTase activity significantly. The immobilized cells produced CGTase with higher activity in a shorter fermentation time comparing to free cells.

A new wood-flour-based photocatalytic composite of wood flour/β-cyclodextrin/titanium dioxide (WF/β-CD/TiO2) was synthesized via the photoinduced assembly method. For evaluation of the photocatalytic efficiency of methyl orange (MO) by WF/β-CD/TiO2, three materials of TiO2, β-CD/TiO2 and WF/TiO2 were prepared and assessed under the same photocatalytic conditions. The morphology of these composites was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM), respectively. The chemical composition was detected by X-ray photoelectron spectroscopy (XPS). By means of phenolphthalein probe technique and back titration method, the contents of active β-CD (3.5 %) and TiO2 (0.0581 g/0.1 g) in the prepared WF/β-CD/TiO2 composite were obtained. In the experiments of photocatalytic reaction, for completely degradation of 0.1 mmol L−1 MO, the degradation time of WF/β-CD/TiO2 was similar to that of β-CD/TiO2 but shorter than those degraded by pure TiO2 and WF/TiO2. The kinetics of photocatalytic degradation of MO by WF/β-CD/TiO2 was also investigated. The intraparticle diffusion kinetic model gave a better correlation for the photocatalytic reaction. In addition, after recycling for five times, the degradation efficiency of MO by WF/β-CD/TiO2 was still above 86 %, which was obviously higher than that by WF/TiO2, indicating a good regeneration property.

Background Bloodstains often constitute the major physical evidence in criminal investi-gations. In many cases, the bloodstains found by the crime scene examiner are minute, possibly because of dissimulation efforts by the perpetrator to eliminate evidence that reveals his identity. In such cases, short tandem repeat (STR) detection procedures must be performed using the same minute bloodstain evidence on which presumptive tests had been performed earlier. In the present study, two of the most often used presumptive test reagents, phenolphthalein and leucomalachite green, were tested to determine their effects on the ability to obtain STR profiles from minute bloodstains. Methods Dried minute bloodstains obtained from 10 donors were treated with phenolphthalein and leucomalachite green. After various times, genomic DNA was extracted from the treated samples using a QIAamp DNA Micro Kit. DNA was quantified with real-time PCR using a Quantifiler Kit. STR loci were amplified using an AmpFLSTR Identifiler Plus Kit, and the amplified products were separated via capillary electrophoresis in a 3130 Genetic Analyzer. Results Full DNA profiles were obtained from all minute bloodstain samples treated with phenolph-thalein when extracted after intervals ranging from 1 h to 1 week. In contrast, the DNA in minute bloodstain samples treated with leucomalachite green was severely degraded, especially after relatively long intervals, leading to poor partial DNA profiles. Conclusion Phenolphthalein is recommended as a safe presumptive test reagent for the detection of blood evidence recovered from crime scenes that might subsequently undergo DNA profiling analysis.

To understand the curing processes of phenolphthalein–aniline-based benzoxazine (BP-a), the curing kinetics of bisphenol A-aniline-based benzoxazine and BP-a were investigated using non-isothermal differential scanning calorimetry (DSC) at different heating rates. Kissinger, Ozawa, Friedman and Flynn–Wall–Ozawa methods were used to determine the kinetic parameters and built the kinetic models. According to the results, BP-a displays two dominant curing processes, namely the autocatalytic curing process at low-temperature curing (reaction (1)) with the average activation energy of 95.0–98.5 and nth-order curing process at elevated temperature curing (reaction (2)) with the average activation energy of 124.0–126.2 kJ mol−1. Moreover, the predicted curves from the kinetic models fit well with the non-isothermal DSC curve. Non-isothermal differential scanning calorimetry is a promising method to help researchers explore the application of BP-a and other arylamine Mannich bridge structures containing polybenzoxazines.

High-substituted 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) was shown to self-assemble in aqueous solutions in the presence of in situ-formed insoluble species of iron. Two different types of water-soluble high-molecular compounds were synthesized at room temperature in aqueous aerated alkaline solutions of (NH4)2Fe(SO4)2•6H2O and high-substituted 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) in the presence of NaH2PO2. These substances called adducts proved to be inorganic-organic hybrid nanospecies of iron species, HP-β-CD and encapsulated inorganic salts (sulfates and phosphates of sodium and ammonium). The adducts were established to show different properties and to have diverse compositions depending on the HP-β-CD: Fe molar ratio in starting solution. The first synthesized adduct (I) is characterized by an unambiguous magnetism with lower solubility in water. It gives a homogeneous solution with particles 400 nm in diameter. The second adduct (II) is not magnetic, more soluble in water, and forms nanoparticles of ∼760 nm in diameter. Both adducts are stable in aqueous solutions but totally destroyed in the presence of H2O2, K2S2O8, and AgNO3. By addition of BaCl2 excess to the aqueous solutions of I and II, the residue of BaSO4 is precipitated and dimensions of the particles of both types decrease up to ∼230 and ∼570 nm in diameter, respectively. Solids I and II were characterized by the data of X-ray diffraction (XRD), Mossbauer spectroscopy, SEM, IR-spectra, and magnetic measurements. Aqueous solutions of I and II were studied by means of mass-spectrometry (MALDI-TOF), dynamic light scattering (DLS) measurements, and analyzed by spectrophotometric titration with phenolphthalein.

Unilateral magnetic resonance was used to obtain the CPMG T 2 decay at different positions along 6 cm long cement paste samples. The aim was to detect the carbonation front based on changes in the pore structure caused by accelerated carbonation and to compare the results with the phenolphthalein test. Cement pastes at water-to-cement ratios of 0.60, 0.50, and 0.40 were prepared using ordinary Portland cement. After moist curing and conditioning at 65% RH and 35 °C, the pastes were subjected to accelerated carbonation with 4% by volume CO2 at 65% RH and 35 °C. Carbonation increases the magnetic resonance T 2 lifetime compared with the control and compared with the noncarbonated region of the samples. A reduction in porosity and changes in the pore size distribution are caused by carbonation. The position with the highest rate of T 2 change was consistent with the fully carbonated front determined by the phenolphthalein test.

This paper addresses the effects of relative humidity (RH) and carbon dioxide (CO2) concentration on the rate and effects of accelerated carbonation in alkali-activated slag/metakaolin (MK) concretes. Strength and water absorption are used alongside phenolphthalein measurements to monitor carbonation, and the effects of drying at different RHs are particularly significant in controlling carbonation rates. Different trends in the carbonation rate as a function of MK content are observed when varying the CO2 concentration, further revealing that the carbonation rates of these materials under accelerated conditions are influenced strongly by the testing protocol. The standard phenolphthalein method for testing carbonation depth appears only to be capturing the change in alkalinity with pore solution carbonation, meaning that it does not correlate well with other performance parameters at high CO2 concentrations.

The characterization, inclusion complexation behavior and binding ability of the inclusion complexes of dihydroartemisinin with β-cyclodextrin and its derivatives, sulfobutyl ether β-cyclodextrin (SBE-β-CD), mono[6-(2-aminoethylamino)-6-deoxy]-β-cyclodextrin (en-β-CD) and mono{6-[2-(2-aminoethylamino)ethylamino]-6-deoxy}-β-cyclodextrin (dien-β-CD), were studied using phenolphthalein as a spectral probe. Spectral titration was performed in aqueous buffer solution (pH ca. 10.5) at 25 °C to determine the binding constants. The inclusion complexation behaviors were investigated in both solution and solid state by means of NMR, TG, XRD. The results showed that the water solubility and thermal stability of dihydroartemisinin were significantly increased in the inclusion complex with cyclodextrins (CDs). According to 1H NMR and 2D NMR spectroscopy (ROESY), the A, B rings of dihydroartemisinin can be included into the cavity of CDs. The enhanced binding ability of CDs towards dihydroartemisinin was discussed from the viewpoint of the size/shape-fit concept and multiple recognition mechanism between host and guest.

The preparation, characterization, and environmental application of β-cyclodextrin/citric acid/wood flour (β-CD/CA/WF) graft copolymer wood-based biosorbent for methylene blue (MB) biosorption were investigated in this paper. The Fourier transform infrared spectroscopy and the technique of phenolphthalein probe were used to characterize the grafting β-CD. Furthermore, the biosorption behavior of MB on β-CD/CA/WF graft copolymer was studied under various conditions of pH, contact time, and initial MB concentration. The results indicated that the biosorption of MB was dependent on both the initial MB concentration and the initial pH. Langmuir isotherm model fitted the isotherm data better than the Freundlich model. The adsorption kinetics followed the pseudo-second-order kinetic model, and intraparticle diffusion was one of the effective rate-controlling steps for the entire biosorption period. Equilibrium and kinetic results have implied that β-CD/CA/WF graft copolymer could be considered as a promising material for the adsorption of dye from aqueous solutions.

A novel functional material of β-cyclodextrin (β-CD) grafting cellulose beads containing immobilized silver nanoparticles (AgNPs) is presented in this paper. The morphology was characterized by scanning electron microscopy, energy-dispersive X-ray, and X-ray photoelectron spectroscopy. Phenolphthalein probe molecule technique was used to detect the activity of the grafting β-CD, and the results demonstrated that the deposition of AgNPs had no influence on its encapsulation ability. Acid resistance of the AgNPs on the bead material was studied by atomic absorption spectrometry. The stability of the AgNPs was enhanced due to the grafting of β-CD. Tube dilution method was applied to study the bacteriostatic effect, and the minimal inhibitory doses of the novel material against Escherichia coli and Staphylococcus aureus were 12.5 and 25 mg, respectively. The minimal bactericidal doses for the two bacteria were 25 and 25 mg, respectively.

Poplar wood flour, a low-cost and abundantly available material, was modified by grafting β-cyclodextrin (β-CD) in the presence of citric acid or 1,2,3,4-Butanetetracarboxylic acid, aiming to expand the application of wood flour. The products were characterized by Fourier transform infrared spectroscopy and the technique of phenolphthalein probe. The grafting conditions of β-CD onto wood flour including curing temperature, β-CD concentration in impregnation solution and catalyst were also evaluated by the technique of phenolphthalein probe. Besides, eugenol (EG), an antibacterial fragrant guest molecule, was loaded on the modified wood flour by lyophilization, and its release characteristics were investigated by Thermo-gravimetric. The results revealed that the modified wood flour material had a thermo-protective effect on the volatilization of EG and the encapsulated EG content was reached to 1.31 %, which could demonstrate a potential application in the finishing and packing areas.

The novel phenolphthalein benzoxazine–benzoic acid (PBB) was synthesized. The structure of the monomer was supported by FTIR, 1H-NMR, and elemental analysis. The curing behavior of PBB–bisoxazoline (1,3-PBO) resin was monitored by FTIR and differential scanning calorimetry. It was found that PBB–bisoxazoline resin exhibited two-stage polymerization mechanism. The thermogravimetry showed that PBB–bisoxazoline resin had good heat resistance due to the rigidity of PBB polymer chains and the high cross-linking density of copolymer. Furthermore, it seemed that the reaction between PBB and 1,3-PBO also led to an additional cross-linking, which increased the cross-linking density and delayed the decomposition. The cured resin had low water absorption.

The dynamics of liposome solubilization was monitored by dynamic light scattering and optical microscopy. A newly designed Y-shape microchannel connected to a room was incorporated into a microchip and the reaction processes of the liposome suspension and surfactant solution were observed in the room after mixing the two fluids and stopping the flow. By using this microchip, we succeeded in real-time monitoring of liposome solubilization and the following dynamic processes of solubilization were proposed: 1) Deformed liposomes become spherical. 2) The liposome size increases until the surfactant/liposome ratio in the liposome membrane reaches a threshold value. 3) Mixed micelles of surfactants and phospholipids are released and the liposomes collapse.

Coumarin and 7-hydroxycoumarin (7HC) were photo-dimerized in an aqueous solution of polymeric β-cyclodextrin (PβCD) to investigate the effect of the photo-dimerization on the viscosity of PβCD solution. PβCD was prepared by cross-linking β-cyclodextrin (βCD) using epichlorohydrin. The content of βCD residues in PβCD, determined by a colorimetric method using phenolphthalein as an indicator, was 28.8 wt%. The solubility of coumarin increased with increasing concentration of PβCD, because the benzene ring of coumarin was included in the hydrophobic cavity of βCD residue. PβCD also increased the solubility of 7HC, but the solubilizing effect on 7HC was much less than that on coumarin, possibly because the hydroxy group on the benzene ring was likely to suppress the inclusion in the cavity of βCD. And, the photo-dimerization degree of 7HC in an aqueous solution of PβCD was about half than that of coumarin, possibly because the vinyl ether of pyrone group of 7HC could be concealed in the cavity of βCD. The photo-dimerization of coumarin in an aqueous solution of PβCD could significantly increase the viscosity of the solution. One coumarin dimer would hydrophobically interact with two βCD residues so it can act as a cross-linker for PβCD.

Pai You Guo is a weight loss supplement manufactured in China and adulterated with the banned pharmaceutical products sibutramine and phenolphthalein. The US Food and Drug Administration (FDA) announced a voluntary recall of Pai You Guo in 2009, yet clinicians have noted its continued use among Brazilian-born women in Massachusetts.To assess prevalence of Pai You Guo use, associated side effects, modes of acquisition, and impact of FDA regulatory action on these outcomes.Cross-sectional study using an anonymous questionnaire.Women ≤60 years of age, born in Brazil who attended one primary care clinic or one of six churches in Massachusetts.Prevalence of use, how users first heard about the product, location of purchase, associated side effects, patterns of use before and after the FDA recall.Twenty-three percent (130/565) of respondents reported using Pai You Guo. In multivariate analysis, obesity (adj OR 3.7, p-value0.001) and lack of insurance (adj OR 2.6, p-value 0.005) were associated with use. The majority of users (85%) reported at least one side effect. Dry mouth (59%), anxiety (29%), and insomnia (26%) were most commonly reported adverse effects. Nearly thirty-percent of users (38/130) purchased Pai You Guo from local stores and 9% (11/130) purchased it over the Internet. The majority of respondents (79/130; 61%) purchased Pai You Guo after the FDA recall. No respondent was aware of the FDA recall.Use of this pharmaceutically adulterated supplement is common among Brazilian-born women in Massachusetts. The FDA alerts and recall did not appear to decrease its use.

To assess the erosive potential of 94 pediatric medicines of various therapeutic groups in vitro.In vitro measurement of endogenous pH and titratable acidity (mmol) of 94 formulations was done. Endogenous pH was measured using a pH meter, followed by titration with 0.1-M NaOH using phenolphthalein as indicator.Overall, 55 (59%) formulations had an endogenous pH of5.5. The mean (±SD) endogenous pH and titratable acidity for 45 SC formulations were 5.52 ± 1.18 and 0.165 ± 0.131 mmol, respectively; for 49 sugars-free (SF) formulations, these figures were 5.81 ± 1.43 and 0.393 ± 1.225 mmol (P 0.05).Compared with their SC bioequivalents, eight SF medicines showed no significant differences for pH or titratable acidity, while 10 higher-strength medicines showed lower pH (P 0.035) and greater titratable acidity (P 0.026) than their lower-strength equivalents. Chewable and dispersible tablets, gastrointestinal medicines and antibiotics were significant predictors of higher pH. In contrast, effervescent tablets, and nutrition and blood preparations were significant predictors of higher titratable acidity.Pediatric SF medicines were not more erosive than SC medicines in vitro; a more significant predictor of their erosive potential was dose form. Higher the dose form more was the erosive potential of the medicine.

A pure benzoxazine synthesized from phenolphthalein through Mannich reaction, 3,3′-bis(3,4-dihydro-3-phenyl-2H-1,3-benzoxazinyl)-1(3H)-isobenzofuranone (Boz-BP), was characterized by FTIR and 1H NMR. Its curing behavior was different with that of 2,2′-bis(4-phenyl-3,4-dihydro-2H-1,3-benzoxazinyl)isopropane (Boz-BA) because Boz-BP possesses highly steric and inactivated phenol rings. During curing period, the reactivity of ortho position of phenolic hydroxyl group was retarded and the addition of -CH2- group generated in ring-opening reaction preferred to taking place on para position of aniline ring, which is beneficial for better thermal properties. Furthermore, additional hydrogen bonding would be formed between carbonyl groups on phthalide structure and hydroxyl groups in Boz-BP based polymer (P(Boz-BP)). Compared with the analogous polymer from Boz-BA (P(Boz-BA)), P(Boz-BP) displayed higher glass transition temperature, better thermal stability, better dimensional stability and flame-retardant properties.

Investigation at the scene of a crime begins with the search for clues. In the case of bloodstains, the most frequently used reagents are luminol and reduced phenolphthalein (or phenolphthalin that is also known as the Kastle-Meyer colour test). The limitations of these reagents have been studied and are well known. Household cleaning products have evolved with the times, and new products with active oxygen are currently widely used, as they are considered to be highly efficient at removing all kinds of stains on a wide range of surfaces. In this study, we investigated the possible effects of these new cleaning products on latent bloodstains that may be left at a scene of a crime. To do so, various fabrics were stained with blood and then washed using cleaning agents containing active oxygen. The results of reduced phenolphthalein, luminol and human haemoglobin tests on the washed fabrics were negative. The conclusion is that these new products alter blood to such an extent that it can no longer be detected by currently accepted methods employed in criminal investigations. This inability to locate bloodstains means that highly important evidence (e.g. a DNA profile) may be lost. Consequently, it is important that investigators are aware of this problem so as to compensate for it.

Three types of host molecules 1–3 based on a phenolphthalein (one of the most popular pH indicators) and two crown ethers were prepared for use in colorimetric recognition of linear diamines, triamines, sequence of non-protected dipeptides in methanol or water solution.

A novel method was developed for enrichment and separation of trace mercury using phenolphthalein modified by ethyl violet (EV). The effects of different parameters, such as stirring time, various metal ions and salts, and the amounts of phenolphthalein, NH 4 SCN, and EV on the extraction rate of mercury were studied, to select the experimental conditions. Under optimum conditions, mercury can be adsorbed on the surface of microcrystalline phenolphthalein by the intermolecular action strength. The possible reaction mechanism for the enrichment of mercury was discussed in detail. Hg(II) could be completely separated from Fe(II), Co(II), Ni(II), Mn(II), Cd(II), Cr(III), and AI(III) in the solution. The proposed method has been successfully applied to the determination of trace mercury in industrial wastewater with the recoveries above 99%. The relative standard deviation for five replicate determinations of 0.04 μg·mL −1 of Hg(II) was found to be 1.4%, 1.1%, and 1.2%, respectively. The analytical results were very satisfactory.

Grafting of cyclodextrins and cyclodextrins derivatives on cellulosic surface, such as paper or filter paper, provides hosting cavities that can include a large variety of chemicals for specific cellulose finishing. In this study grafting of monocholorotriazinyl-β-cyclodextrin (MCT-β-CD) and β-cyclodextrin (β-CD) to filter paper has been performed. β-cyclodextrin has been bonded to filter paper using 1,4-butanediol diglycidyl ether as the crosslinking agent. The untreated and treated filter papers were characterized by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), demonstrating the covalent binding of cyclodextrins to filter paper. The quantification of β-CD and MCT-β-CD grafted to filter paper was determined by the dye extinction method with the inclusion of phenolphthalein. The final β-CD content amounted to 15.9 μmol per gram of support (1.8% by weight), and 72.8 μmol per gram of support (11.3% by weight) for MCT-β-CD.

Several β-cyclodextrin polymers (βCDP) have been obtained by cross-linking β-cyclodextrin (βCD) with the reagent epichlorohydrin (EP). It is expected that these polymers are capable of retaining different organic molecules by adsorbing them on its network and also by forming inclusion complexes with βCDs. In this work, two soluble polymers containing 39% and 48% βCD and other insoluble ones with 65% and 74% βCD have been studied. The total amount of CD in the polymers could not be available for complexation. This parameter has been calculated by means of the decrease of colour intensity of phenolphthalein solutions when different amounts of βCDP were added. The insoluble polymer with 74% βCD appears to possess less CD available than that with 65% βCD, probably due to the higher cross-linking degree of the former. On the other hand, a higher availability of CD is found for the soluble polymer which contains 48% βCD. Moreover, the amount of glycerol monoether groups formed as a side effect during the cross-linking process has been determined and related to the epichlorohydrin content, structure and swelling properties of the polymers. It is concluded that, varying the synthesis conditions, it is possible to induce structural modifications in the hydrogel networks which can improve their practical applications.

A new method of using phenolphthalein loaded with 1-(2-pyridylazo)-2-naphthol (PAN) as solid phase extractant to separate and enrich trace copper in diverse water samples has been developed. The ef-fects of different parameters, such as the amounts of PAN and phenolphthalein, stirring time, various salts and metal ions on the enrichment yield of Cu(II) have been investigated to select the experimental conditions. Under the optimum conditions, Cu(II) can be totally adsorbed on the surface of microcrys-talline phenolphthalein. By controlling appropriate acidity (pH=1.0), Cu(II) is completely separated from Cd(II), Pb(II), Mn(II), Co(II), Fe(III), Ni(II), Al(III), Zn(II) and Hg(II) in the solution. The possible reaction mechanism of the enrichment of copper is discussed in detail in this paper. The detection limit of this proposed method is found to be 0.03 mg·L-1 with the enrichment factor of 200. The recovery is in a range of 96.8%―105%. The standard deviation is less than 2.5%. The proposed method has been successfully applied to the determination of trace copper in different water samples with satisfactory results.

A simple sequential injection analysis (SIA) with spectrophotometric detection for an assay of acidity in fruit juice was investigated. An alkaline reagent (sodium hydroxide), a sample and an indicator (phenolphthalein) were first aspirated and stacked as adjacent zones in a holding coil. With flow reversal through a reaction coil to the detector, zone penetration occurred, leading to a neutralization reaction that caused a decrease in the color intensity of the indicator being monitored for absorbance at 552 nm. The effects of various parameters were studied. Linear calibration graphs for acidities of 0.2 - 1.0 and 0.5 - 2.5% w/v citric acid as a standard, with a relative standard deviation of 1% (acidity of 0.3 - 0.6% w/v as citric acid, n=11) and a sample throughput of 30 samples h(-1), were achieved. The developed method was validated by a standard titrimetric method for assaying the acidity of fruit juice samples.

The binding constants, K′, for the reaction between some alkyldimethylbenzylammonium bromide homologues (alkyl = methyl, ethyl, propyl, butyl, hexyl, decyl, and dodecyl, respectively) and β-cyclodextrin in water at 25.0 ± 0.1 ∘C have been determined, by applying the spectral displacement technique with phenolphthalein as the displacing anion. It has been shown that the ln K′ values increase linearly with the number of carbon atoms in the alkyl chain for the salts whose alkyl chain has at least four carbon atoms. The ln K′ values estimated for the parent compound benzyltrimetylammonium bromide and its two nearest homologues are distinctly lower than might be expected by extrapolation of the linear relation found for the higher homologues. Assuming that it is the organic cation that undergoes association with β-cyclodextrin, then one may suppose that a change occurs in the mode of inclusion of the cation upon passing to higher homologues. In the case of the lighter homologues, it is the phenylene group that undergoes inclusion. This model of inclusion is confirmed by analysis of rotating-frame overhauser effect spectroscopy (ROESY) spectra.

Phenolphthalein-glucuronide is a commonly used glucuronide conjugate for beta-glucuronidase measurements. The quantity of phenolphthalein liberated by beta-glucuronidase is measured spectrophotometrically. The detection limit of the quantity of phenolphthalein using spectrophotometry is a few μg. In this study, a new radioanalytical technique for the measurement of beta-glucuronidase was applied which is 106times more sensitive than the spectrophotometric technique. Radioiodinated phenolphthalein-glucuronide and phenyl-N-glucuronide were used in this study in which the beta-glucuronidase levels of some tissue samples were measured.

4,4′-Oxydiphthalic anhydride (1) was reacted with L-methionine (2) in acetic acid and the resulting N,N′-(4,4′-oxydiphthaloyl)-bis-L-methionine diacid (4) was obtained in high yield. The direct polycondensation reaction of this diacid with several aromatic diols such as bisphenol A (5a), phenolphthalein (5b), 1,4-dihydroxyanthraquinone (5c), 4,4′-dihydroxydiphenyl sulfide (5d), 2,6-dihydroxytoluene (5e), 4,4′-dihydroxydiphenyl sulfone (5f) and 2,4′-dihydroxyacetophenone (5g) was carried out in a system of tosyl chloride (TsCl), pyridine (Py) and N,N-dimethylformamide (DMF). The reactions with TsCl were significantly promoted by controlling alcoholysis with diols in the presence of the catalytic amounts of DMF to give a series of optically active poly(ester-imide)s (PEI)s with good yield and moderate inherent viscosity ranging 0.21–0.71 dL/g. The polycondensation reactions were significantly affected by the amounts of DMF, molar concentration of monomers, TsCl and pyridine, aging time, addition time of diols, temperature and the reaction time. All of the above polymers were fully characterized by 1H-NMR, FT-IR, elemental analysis and specific rotation. Some structural characterization and physical properties of these new optically active PEIs are reported.

By reacting esterification of phenolphtalein with methacrylate chloride, phenolphtalein dimethacrylate was obtained. Based on the results of elemental analysis, FTIR, 1H-NMR and 13C-NMR spectra, the structure of the product was proposed. The dimethacrylate was used as new crosslinker to crosslink poly(methyl methacrylate) (PMMA). The influence of the amount dimethacrylate on the crosslink density and some properties of the crosslinked polymers networks such as swelling, mechanical properties (tensile strength and elongation at break) and thermal stability were examined.

A novel fluorinated diamine monomer, 3,3-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]phthalide (II), was prepared through the nucleophilic substitution reaction of 2-chloro-5-nitrobenzotrifluoride with phenolphthalein in the presence of potassium carbonate to yield the intermediate dinitro compound I, followed by catalytic reduction with hydrazine and Pd/C. Polyimides V were synthesized from diamine II and various aromatic dianhydrides IIIa–f via thermal or chemical imidization of poly(amic acid)s. These polymers had inherent viscosities ranging from 0.63 to 0.95 dL/g and were soluble in a variety of organic solvents. Va–f films had tensile strengths of 105–125 MPa, elongations to break of 9–12%, and initial modulus of 2.35–2.65 GPa. The glass transition temperatures of these polymers were recorded 259–320 °C, and no significant weight loss was observed below a temperature of 500 °C in nitrogen or in air. Compared with nonfluorinated homologues VI, V showed better solubility and lower color intensity, dielectric constant (2.70–3.11 at 1 MHz), and moisture absorption (0.12–0.27 wt %). In particular, Vc–f afforded lightly colored films, which had cutoff wavelengths lower than 380 nm and yellowness index (b* values) ranging from 9 to 25. On comparing thermal imidized polymers with chemical imidized ones, films Va–f(C) showed a lower color intensity than Va–f(H) did.

Cyclodextrins and some of their water-soluble derivatives form with phenolphthalein host-guest complexes whose stability depends on the structure, position, and number of substituents.

Poly(arylene ether ketones) with preset molecular weights (reduced viscosity from 0. 2 to 0.82 dL g−1) containing terminal phenolic groups were synthesized by the reactions of 4,4′-difluorobenzophenone with bisphenol A or phenolphthalein in the presence of K2CO3 in N,N-dimethylacetamide. The influence of an excess of bisphenols on the molecular weights of the polymers obtained was studied. The structures of the polymers were confirmed by 1H NMR spectroscopy. The molecular weight distributions of the polymers were determined.