Hydrated and anhydrous zinc borate fillers for tuning the flame retardancy of epoxy nanocomposites

In this study, hydrous (Zn₃B₆O₁₂·3.5H₂O) and anhydrous (ZnB₂O₄) forms of zinc borates were synthesized at 150 and 175°C under moderate pressure conditions (85 and 150 psi, respectively). Synthesized zinc borates were controllably incorporated (1, 5, and 10 wt%) in epoxy resin to prepare their nanocomposites. The flame-retardant and mechanical properties of these nanocomposites were determined and compared in terms of their flame spread testing, smoke density, limiting oxygen index, and flexural strength. Superior properties in terms of flame retardancy were observed for epoxy composites containing hydrous filler as compared to anhydrous zinc borates. Although flexural strength was observed to be decreased with increasing filler concentration, the marked drop is lower for composites with hydrous zinc borate as compared to the anhydrous one. The variations in flame-retardant and mechanical properties of composites with both types of fillers are related to their morphological (field emission scanning electron microscopy), X-ray diffraction (XRD) analysis, Fourier Transform Infrared (FTIR), differential scanning calorimetry, and thermogravimetry analysis and explained with condensed phase mechanism.     

Preparation of ferric phosphonate/phosphinate and their special action on flame retardancy of epoxy resin

Fe‐ and P‐based compounds have demonstrated promising performance in enhancing flame retardancy of epoxy resins. In this context, this work focuses on the preparation of new Fe/P hybridized nanomaterials and their effect on flame retardancy of epoxy resins. The Fe/P hybrids were facilely prepared via forming ferric phosphinates and phosphonates using hydrothermal reaction. Attractively, ferric phosphinates and phosphonates exhibit the morphology of 1D nanorod and 2D nanosheet, respectively. When incorporating these two fillers in epoxy resin, the limiting oxygen index values of composites were enhanced to above 28 and the composites exhibited self‐extinguishing behavior, thus indicating greatly improved fire resistance. Further investigation revealed that the flame retarding behavior, in particular for ferric phosphonate nanosheets, took place mainly in gas phases via delaying the release of flammable gas. Attractively, it was found that the Fe/P hybrids took part into the pyrolysis reaction of epoxy resins through forming Fe? O and P? O bonds. This finding may provide a new insight to design a series of high performance flame retardants for epoxy resins. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46206.     

Preparation of alginate flame retardant containing P and Si and its flame retardancy in epoxy resin

In the present paper, a novel biomass flame retardant based on alginic acid was synthesized through chemical combination with a reactive P–Si compound. Compared with alginates, the modified alginate showed obviously increased thermal stability and water resisting property, as well as better compatibility with epoxy resin, which can satisfy the requirements of a flame‐retardant additive in the polymer. The flame‐retardant properties were evaluated by vertical burning tests, limiting oxygen index, and microscale combustion calorimetry. Due to the self‐charring capacity of alginate combined with the charring catalyst from P and the charring reinforcer from Si, the modified alginate exhibited much better flame retardancy, taking advantage of the formation of a more continuous, denser, and strengthened char layer than either individual alginate or P–Si flame retardant. The corresponding flame‐retardant mechanisms were investigated and discussed. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45552.     

Study on flame retardancy of APP/PEPA/MoO3 synergism in vinyl ester resins

A range of flame retardant vinyl ester resins (VERs) samples have been produced containing different contents of PEPA (1-oxo-4-hydroxymethyl-2,6,7-trioxa-l-phosphabicyclo[2.2.2]octane), APP (ammonium polyphosphate), and MoO₃ (molybdenum trioxide). By investigating the flame retardancy of VER samples such as limiting oxygen index and UL-94, the synergistic flame retardance of APP, PEPA, and MoO3 has been revealed. The cone calorimeter is an instrument that measures the combustion data of samples. In the VER composites on fire, the synergistic smoke suppression effect of the APP, PEPA, and MoO₃ was detected. The gas and condensed phase of VER composites with APP, PEPA, and MoO₃ were tested by the thermogravimetric analysis (TGA)–Fourier transform infrared spectroscopy (FTIR) and FTIR. The char residues of samples have been studied at length by scanning electron microscopy and FTIR. The results show that the presence of MoO3 can promote the formation of P O and PO structures.     

Polyamide‐enhanced flame retardancy of ammonium polyphosphate on epoxy resin

An attractive intumescent flame retardant epoxy system was prepared from epoxy resin (diglycidyl ether of bisphenol A), low molecular weight polyamide (cure agent, LWPA), and ammonium polyphosphate (APP). The cured epoxy resin was served as carbonization agent as well as blowing agent itself in the intumescent flame retardant formulation. Flammability and thermal stability of the cured epoxy resins with different contents of APP and LWPA were investigated by limited oxygen index (LOI), UL‐94 test, and thermogravimetric analysis (TGA). The results of LOI and UL‐94 indicate that APP can improve the flame retardancy of LWPA‐cured epoxy resins. Only 5 wt % of APP can increase the LOI value of epoxy resins from 19.6 to 27.1, and improve the UL‐94 ratings, reaching V‐0 rating from no rating when the mass ratio of epoxy resin to LWPA is 100/40. It is much interesting that LOI values of flame retardant cured epoxy resins (FR‐CEP) increase with decreasing LWPA. The results of TGA, FTIR, and X‐ray photoelectron spectroscopy (XPS) indicate that the process of thermal degradation of FR‐CEP consists of two main stages: the first stage is that a phosphorus rich char is formed on the surface of the material under 500°C, and then a compact char yields over 500°C; the second stage is that the char residue layer can give more effective protection for the materials than the char formed at the first stage do. The flame retardant mechanism also has been discussed according to the results of TGA, FTIR, and XPS for FR‐CEP. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Effect of graphite on the flame retardancy and thermal conductivity of P‐N flame retarding PA6

In this article, a novel flame‐retardant polyamide 6 (PA6) was prepared by introducing a halogen‐free flame‐retardant (OP1314). Graphite was added as a flame‐retardant synergistic agent, and the flame retardancy was enhanced, especially the melt‐dripping was forbidden and for the formula of PA6/12 wt % OP1314/5 wt % graphite, UL94 V‐0 grade was reached. Meanwhile, the graphite is also an excellent thermal conductive filler and with the addition of 5 wt % graphite in the flame‐retardant PA6 mixtures, the thermal conductivity (λ) rose to 1.2 W/mK which was nearly three times higher than the flame‐retardant PA6. Due to the good flame retardancy and improved thermal conductivity, the material could be suitable for applications in electronic and electrical devices. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46559.     

Novel strategy for molybdenum disulfide nanosheets grown on titanate nanotubes for enhancing the flame retardancy and smoke suppression of epoxy resin

A novel hybrid consisting of a molybdenum disulfide (MoS₂) coating on a titanium dioxide nanotube (TNT) surface (MoS₂–TNT) was synthesized by a hydrothermal method. The MoS₂, TNTs, and MoS₂–TNT hybrid were incorporated into epoxy resin (EP) to study their effects on its thermal performance and flame retardancy. Thermogravimetric analysis results show that the char yield at 700 °C of EP–MoS₂–TNTs was obviously increased compared with that of the EP–MoS₂ or EP–TNTs; this indicated that MoS₂–TNTs had a good carbonization effect. The limiting oxygen index, cone calorimetry, and smoke density tests showed that MoS₂–TNTs effectively improved the flame retardancy and smoke suppression of EP. This was attributed to the physical barrier effect of MoS₂ and the adsorption of TNTs. Moreover, the flame retardancy and smoke suppression of the EP–MoS₂–TNTs were better than those of the EP–MoS₂ or EP–TNTs alone with the same amount of addition; this indicated that there was a synergistic effect between MoS₂ and TNTs. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46064.     

Synthesis and characterization of dicyclic silicon-/phosphorus-grafted alumina and its application in improving flame retardancy of epoxy resin

A new phosphorous/silicon/aluminum hybrid flame retardant (SAlu) was prepared by a surface grafting modification of alumina with a polymer (SDPS). The polymer was prepared by a condensation reaction between 3,9-dichloro-2,4,8,10-tetrahydroxy-3,9-diphosphate heterocyclic-3,9-dioxide [5.5] undecane (SPDPC) and diphenyldisiloxol. The structure of the SAlu was further characterized by Fourier transform infrared spectroscopy, X-ray diffraction, UV–Vis absorption, and particle size analysis. Thermogravimetric analysis showed that SPDS was grafted over 40% of the alumina surface. When introduced into epoxy resin, SAlu effectively improved the thermal stability and carbonization rate of the epoxy composites at high temperature. Carbonization studies showed that SAlu promoted formation of a ceramic-carbon coking structure with a porous morphology of aggregates, which isolate combustible materials, heat, and oxygen. These features improved the flame retardant performance of the composite. The solidified materials were evenly dispersed in the network structure to improve the elastic deformation ability and glass transition temperature of the solidified resin.     

Transparent epoxy resin material with excellent fire retardancy enabled by a P/N/S containing flame retardant

An epoxy resin (EP) with excellent fire retardancy, good transparency, and satisfactory thermal stability has been obtained by introducing a new N/P/S containing flame retardant (HBD) into EP composites. When the phosphorus content was 0.48 wt%, EP/HBD reached V-0 rating with the limiting oxygen index of 33.5%. The cone calorimeter test (CC) indicated that the incorporation of HBD resulted in 1.5 times increase in ignition time, a 50% decrease in the maximum of heat release rates, 40% reduction of total heat release, and 50.7% decrease in total smoke production compared with EP. Besides, the fire-resistant behavior of EP/8% HBD is much better than the EP materials modified by similar P/N/S flame retardants reported in literature. The fire-retardant mechanism of HBD on EP was also analyzed by Raman, scanning electron microscope, Py-GC/MS, and Fourier transform infrared spectroscopy. The results show that HBD plays an important role in the formation of a dense intumescent carbon layer and gas phase quenching.     

Flame retardancy effects of phosphorus‐containing compounds and cationic photoinitiators on photopolymerized cycloaliphatic epoxy resins

This study presents a promising ultraviolet (UV)‐curable epoxy resin formulation with improved flame‐retardant properties. The formulation is based on the cycloaliphatic epoxide 3,4‐epoxycyclohexylmethyl‐3,4‐epoxycyclohexane carboxylate (ERL4221) and a novel silicon, phosphorous containing flame‐retardant additive. The additive, 1,3,5,7‐tetramethyl‐1,3,5,7‐tetra 2‐(6‐oxido‐6‐H‐dibenzo(c,e) (1,2)oxaphosphorin‐6‐yl) ethylcyclotetrasiloxane (DOPO‐SiD), was synthesized by the addition reaction of 1,3,5,7‐tetramethyl‐1,3,5,7‐tetravinylcyclotetrasiloxane (D₄Vi) with 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO). Formulations containing the cycloaliphatic epoxy resin ERL4221 and the flame‐retardant DOPO‐SiD additive were prepared in various concentrations and crosslinked by UV irradiation. The effects of DOPO‐SiD and photoinitiators, such as the cyclopentadienyl iron complex of carbazole (In‐Fe) and diphenyl‐(4‐(phenylthiol) phenyl) sulfonium hexafluorophosphate (In‐S), on the flame‐retardant properties and thermal stabilities of UV‐cured ERL4221/DOPO‐SiD composites were investigated with limiting oxygen index, UL‐94 vertical test, and thermogravimetric analysis, respectively. The results showed that DOPO‐SiD can increase the thermal stabilities of the ERL4221/DOPO‐SiD. The char yield was improved when DOPO‐SiD and In‐Fe were simultaneously used. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40011.     

Synthesis of a novel phosphorus‐containing dicyclopentadiene novolac hardener and its cured epoxy resin with improved thermal stability and flame retardancy

A novel phosphorus‐containing dicyclopentadiene novolac (DCPD‐DOPO) curing agent for epoxy resins, was prepared from 9,10‐dihydro‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) and n‐butylated dicyclopentadiene phenolic resin (DCPD‐E). The chemical structure of the obtained DCPD‐DOPO was characterized with FTIR, ¹H NMR and ³¹P NMR, and its molecular weight was determined by gel permeation chromatography. The flame retardancy and thermal properties of diglycidyl ether bisphenol A (DGEBA) epoxy resin cured with DCPD‐DOPO or the mixture of DCPD‐DOPO and bisphenol A‐formaldehyde Novolac resin 720 (NPEH720) were studied by limiting oxygen index (LOI), UL 94 vertical test and cone calorimeter (CCT), and differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. It is found that the DCPD‐DOPO cured epoxy resin possess a LOI value of 31.6% and achieves the UL 94 V‐0 rating, while its glass transition temperature (T_g) is a bit lower (133 °C). The T_g of epoxy resin cured by the mixture of DCPD‐DOPO and NPEH720 increases to 137 °C or above, and the UL 94 V‐0 rating can still be maintained although the LOI decreases slightly. The CCT test results demonstrated that the peak heat release rate and total heat release of the epoxy resin cured by the mixture of DCPD‐DOPO and NPEH720 decrease significantly compared with the values of the epoxy resin cured by NPEH720. Moreover, the curing reaction kinetics of the epoxy resin cured by DCPD‐DOPO, NPEH720 or their mixture was studied by DSC. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44599.     

Synthesis of modified graphene oxide and its improvement on flame retardancy of epoxy resin

In this work, the small molecule with double-phosphaphenanthrene structure was successfully grafted on the surface of graphene oxide (GO), which is called functionalized graphene oxide (FGO). The introduction of FGO improved the poor interfacial compatibility between graphene and epoxy matrix. And FGO could be used as the highly effective flame retardant. The thermogravimetric analysis results showed a significant improvement in the char yield of cured FGO/EP. When the content of FGO was 3 wt %, the limiting oxygen index value reached 30.4%. At the same time, the three-point bending and thermomechanical tests confirmed that the mechanical properties of the epoxy resin composites were improved. Based on the char analyses of SEM images and Raman spectroscopy, the flame retardant could promote the formation of a stable carbon layer. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 47710.     

Reactive flame retardant with core‐shell structure and its flame retardancy in rigid polyurethane foam

With a shell of poly (methyl methacrylate‐co‐hydroxyl ethyl acrylate) (PMMA‐HA), microencapsulated ammonium polyphosphate (MHAPP) is prepared by in situ polymerization. The core‐shell structure of the reactive flame retardant (FR) is characterized by Fourier transform infrared (FTIR) and scanning electron microscopy/energy dispersive spectroscopy (SEM/EDS). The results of water leaching rate and water contact angle measurements show that ammonium polyphosphate (APP) is well coated by a hydrophobic shell. Due to the presence of active groups (–OH) and hydrophobic groups (–CH₃) in shell, MHAPP exhibits better compatibility, flame retardancy, and water resistance compared with neat ammonium polyphosphate (APP) in rigid polyurethane foam (PU). Compression strength of PU/MHAPP with suitable loading is higher than that of PU/APP and PU, the reason is that the active groups in shell can improve the compatibility of MHAPP in PU composite. From thermal stability and residue analysis, it can be seen that the presence of reactive flame retardant shows positive effect on thermal stability of PU composite at high temperature, results also indicate that MHAPP can promote the carbonization formation efficiency of PU composite during combustion process compared with APP. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42800.     

Novel phosphorus‐based flame retardants containing 4‐tert‐butylcalix[4]arene: Preparation and application for the fire safety of epoxy resins

A novel flame retardant (FR) containing phosphorus and 4‐tert‐butylcalix[4]arene was synthesized and characterized. The FR combined with ammonium polyphosphate (APP) was then incorporated into epoxy resins (EPs) at different ratios. The flame retardancy, thermal stability, and smoke‐releasing properties were investigated. The limiting oxygen index was as high as 30.8% when the mass fraction ratio of the FR to APP was 1:2. The improved FR effect have been due to the combined FR effects between the FR and APP. The char residue content at 800 °C under a nitrogen atmosphere increased notably from 8.22% to 17.6% when the FR APP was incorporated into EP; this indicated an improvement in the thermooxidation resistance. From the cone test, we found that both the total heat‐release and peak heat‐release rate of the FR resins were reduced. Compared to the resins containing no FRs, the smoke‐production rate and total smoke‐production results indicate that the FR resins also exhibited good smoke‐suppression properties. Generally, the stable char layer of the FR APP–EP not only effectively prevented the release of combustion gases but also hindered the propagation of oxygen and heat into the interior substrate. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45105.     

Synthesis,thermal and mechanical behavior of a silicon/phosphorus containing epoxy resin

A liquid silicon/phosphorus containing flame retardant (DOPO–TVS) was synthesized with 9,10‐dihydro‐9‐oxa‐10‐phosphapheanthrene‐10‐oxid (DOPO) and triethoxyvinylsilane (TVS). Meanwhile, a modified epoxy resin (IPTS–EP) was prepared by grafting isocyanate propyl triethoxysilane (IPTS) to the side chain of bisphenol A epoxy resin (EP) through radical polymerization. Finally, the flame retardant (DOPO–TVS) was incorporated into the modified epoxy resin (IPTS–EP) through sol–gel reaction between the ethyoxyl of the two intermediates to obtain the silicon/phosphorus containing epoxy resin. The molecular structures of DOPO–TVS, IPTS–EP and the final modified epoxy resin were confirmed by FTIR spectra and ¹H‐NMR, ³¹P‐NMR. Thermogravimetric analysis (TGA), differential scanning calorimetry, and limiting oxygen index were conducted to explore the thermal properties and flame retardancy of the synthesized epoxy resin. The thermal behavior and flame retardancy were improved. After heating to 600°C in a tube furnace, the char residue of the modified resin containing 10 wt % DOPO–TVS displayed more stable feature compared to that of pure EP, which was observed both by visual inspection and scanning electron microscope (SEM). Moreover, the mechanical performance testing results exhibited the modified epoxy resins possessed elevated tensile properties and fracture toughness which is supported by SEM observation of the tensile fracture section. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42788.     

An intrinsic flame retardant epoxy resin with high transparency and strengthened mechanical property

In order to search for multifunctional epoxy thermosets (EP) with low flammability, high transparency and satisfied mechanical performance, DOPO-based phosphonate ammonium salt (DOA) was synthesized from 10-hydroxy-9,10-dihydro-9-oza-10-phosphaphenanthrene-10-oxide (DOPO-OH) and 2-amino-2-methyl-1,3-propanediol (AMPD). Under the influence of DOA, the flame-retardant and mechanical performances of the resulting EP were obviously improved. On account of the enhanced interaction and the incorporated flexible fragments in epoxy macromolecular chains, the tensile strength, elongation at break, and impact toughness of EP/5.0 wt% DOA significantly increased from 65.4 ± 1.2 MPa, 6.7 ± 0.6%, and 12.1 ± 1.3 kJ m⁻² of EP to 81.4 ± 2.8 MPa, 10.6 ± 0.5%, and 18.0 ± 1.1 kJ m⁻², respectively. In the presence of DOA, the limiting oxygen index (LOI) value of EP/5.0 wt% DOA increased to 35.5% and it passed the underwriter laboratories-94 vertical burning tests (UL-94 V) and got a V-1 rating. Moreover, the peak value of heat release rate (PHRR) was decreased by 38.0%. The analyses of char residues and volatile products showed that the activities of DOA on reducing the flammability of EP were ascribed to the protective effect of the char, the release of incombustible gases, and the radical-capture action of phosphorus-containing free radicals. Moreover, the modified epoxy thermosets still retained a high transparency.     

A bifunctional modifier endowing epoxy resin with outstanding flame retardancy and high impact strength

The flammability and brittleness are two major shortages of epoxy resin (EP). Normally, adding flame retardants can deteriorate the mechanical property of EP. Herein, in this work, a reactive flame retardant (DPPO-TES) containing both Si and P was synthesized and incorporated into EP. When the content of P is only 1.0 wt%, the LOI of the modified EP (DPPO-TES/EP) reaches to 33.2%, UL-94 passes V0, THR and pk-HRR are 377.6 kw/m² and 103.5 MJ/m², respectively, which is attributed to the high flame-retardant efficiency in both condense phase and gas phase. In addition, the flexible Si O Si chains in the structure can significantly improve the impact strength of DPPO-TES/EP. Therefore, as a bifunctional modifier, DPPO-TES has a wide application prospect for EP materials.     

An effective intumescent flame retardancy of LDPE induced by the combination of APP and CNCO‐HA

A char‐forming agent poly(4,6‐dichloro‐N‐hydroxyethyl?1,3,5‐triazin‐2‐amine‐1,6‐diaminohexane) (CNCO‐HA) containing triazine rings was chosen for improving the flame retardant of low density polyethylene (LDPE). The synergistic effect of CNCO‐HA and Ammonium polyphosphate (APP) on the flame retardancy and char‐forming behavior of LDPE were investigated. The limited oxygen index (LOI) and vertical burning test (UL‐94) results indicated the optimal weight ratio of APP to CNCO‐HA was 3:1, and the LOI value of composite reached 31.0% with 30% intumescent flame retardant (IFR) loading. The cone calorimeter test analysis revealed that IFR presented excellent char forming and smoke suppression ability, and resulted in the efficient decrease of combustibility parameters. The thermogravimetric analysis results demonstrated that IFR reduced the thermal degradation rate at main stage of degradation. Scanning electron microscopy observed that IFR promoted to form a compact and continuous intumescent char layer. The Laser Raman spectroscopy spectra showed that larger graphitization degree was formed to enhance the strength of char, and Fourier transform infrared results presented that P‐O‐C and P‐O‐P structures in the residue char were formed to improve shield performance of the char layer to obtain better flame retardant properties of the composite. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43950.     

Mechanical performance and flame retardancy of polypropylene composites containing zeolite and multiwalled carbon nanotubes

Intumescent‐flame‐retarded polypropylene (PP‐IFR) composites were prepared by the incorporation of methyl hydrogen siloxane treated ammonium polyphosphate and dipentaerythritol in a twin‐screw extruder. The effects of zeolite (Z), multiwalled carbon nanotubes (CNTs), and maleic anhydride grafted polypropylene on the flame retardancy, mechanical properties, and thermal stability of PP‐IFR were investigated. The addition of Z and CNT promoted the flame retardancy of PP‐IFR, and the highest limited oxygen index was 35.6%, obtained on PP‐M‐IFR‐2–Z, for which the heat‐release rate, total heat release, and smoke production rate based on cone calorimetry analyses decreased by 45.0, 51.0, and 66.3%, respectively, in comparison with those values of the PP‐IFR composites. Additionally, scanning electron microscopy analyses showed that there was a good interface interaction between the polypropylene matrix and additives. The flexural, tensile, and impact strengths of the PP‐IFR composites were improved significantly with the incorporation of CNT. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42875.     

Synthesis and characterization of phosphorus‐containing waterborne polyurethanes: Effects of the organophosphonate content on the flame retardancy,morphology, and film properties

A series of waterborne polyurethanes (WPUs) with different contents of reactive organophosphonate were well prepared. Their structures were characterized by Fourier transform infrared and ¹H‐NMR spectroscopy. Thermogravimetry and derivative thermogravimetry revealed that the WPU films containing phosphorus possessed lower onset and maximum degradation temperatures but higher char yields. Differential scanning calorimetry analysis suggested phase mixing of the hard and soft domains. The mechanical properties decreased with increasing amount of organophosphonate, whereas the limiting oxygen index results of the WPU films indicate that the flame retardancy was improved significantly by the incorporation of organophosphonate. The water uptake values of the organophosphonate‐containing WPU films were higher than those of the phosphorus‐free ones, whereas the static contact angles of the films indicated that the surface hydrophilic properties were not affected by segmenting in this phosphorus‐containing oligomer. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008