Synthesis of epoxy‐functionalized hyperbranched poly(phenylene oxide) and its modification of cyanate ester resin

High curing temperature is the key drawback of present heat resistant thermosetting resins. A novel epoxy‐functionalized hyperbranched poly(phenylene oxide), coded as eHBPPO, was synthesized, and used to modify 2,2′‐bis (4‐cyanatophenyl) isopropylidene (CE). Compared with CE, CE/eHBPPO system has significantly decreased curing temperature owing to the different curing mechanism. Based on this results, cured CE/eHBPPO resins without postcuring process, and cured CE resin postcured at 230°C were prepared, their dynamic mechanical and dielectric properties were systematically investigated. Results show that cured CE/eHBPPO resins not only have excellent stability in dielectric properties over a wide frequency range (1–10⁹Hz), but also show attractively lower dielectric constant and loss than CE resin. In addition, cured CE/eHBPPO resins also have high glass transition temperature and storage moduli in glassy state. These attractive integrated performance of CE/eHBPPO suggest a new method to develop high performance resins. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Curing behavior and dielectric properties of hyperbranched poly(phenylene oxide)/cyanate ester resins

A novel hyperbranched poly(phenylene oxide) (HBPPO) modified 2,2′‐bis(4‐cyanatophenyl) isopropylidene (BCE) resin system with significantly reduced curing temperature and outstanding dielectric properties was developed, and the effect of the content of HBPPO on the curing behavior and dielectric properties as well as their origins was thoroughly investigated. Results show that BCE/HBPPO has significantly lower curing temperature than BCE owing to the different curing mechanisms between the two systems, the difference also brings different crosslinked networks and thus dielectric properties. The dielectric properties are frequency and temperature dependence, which are closely related with the content of HBPPO in the BCE/HBPPO system. BCE/2.5 HBPPO and BCE/5 HBPPO resins have lower dielectric constant than BCE resin over the whole frequency range tested, while BCE/10 HBPPO resin exhibits higher dielectric constant than BCE resin in the low frequency range (<10⁴ Hz) at 200°C. At 150°C or higher temperature, the dielectric loss at the frequency lower than 10² Hz becomes sensitive to the content of HBPPO. These phenomena can be attributed to the molecular relaxation. Two relaxation processes (α‐ and β‐relaxation processes) are observed. The β‐relaxation process shifts toward higher frequency with the increase of temperature because of the polymer structure and chain flexibility; the α‐relaxation process appears at high temperature resulting from the chain‐mobility effects. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Flame‐retardant materials based on phosphorus‐containing polyhedral oligomeric silsesquioxane and bismaleimide/diallylbisphenol a with improved thermal resistance and dielectric properties

Polyhedral oligomeric silsesquioxane containing 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DP) was used to flame‐retard 4,4′‐bismaleimidophenyl methane (BDM)/2,2′‐dially bisphenol A (DBA) resins, and the integrated properties of the resins were investigated. The fire resistance of BDM/DBA resins containing DP was analyzed by limiting oxygen index (LOI) and vertical burning (UL94) tests. The results show that DP increased the LOI of the resins from 25.3 to 38.5%. The BDM/DBA resins were evaluated to have a UL‐94 V‐1 rating, which did not satisfy the high standards of industry. On the other hand, BDM/DBA containing DP achieved a UL‐94 V‐0 rating. The thermal stability and char formation were studied by thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy. TGA and scanning electron microscopy–energy‐dispersive X‐ray spectrometry measurements demonstrated that the DP resulted in an increase in the char yield and the formation of the thermally stable carbonaceous char. The results of Raman spectroscopy showed that the DP enhanced the graphitization degree of the resin during combustion. Moreover, the modified BDM/DBA resins exhibited improved dielectric properties. Specifically, the dielectric constant and loss at 1 MHz of the BDM/DBA/15% DP resin were 3.11 and 0.008, respectively, only about 93 and 73% of those of the BDM/DBA resin. All of the investigations showed that DP was an effective additive for developing high‐performance resins with attractive flame‐retardant and dielectric properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41545.     

High performance self‐healing bismaleimide/diallylbisphenol a/poly(phenylene oxide) microcapsules composites with low temperature processability

Novel high performance self‐healing 4,4′‐bismaleimidodiphenylmethane (BDM)/diallylbisphenol A(BA)/poly(phenylene oxide) microcapsules filled with epoxy resin (PPOMCs) systems with low temperature processability were developed. The effects of PPOMCs on the reactivity of BDM/BA resin system were investigated; the properties of cured BDM/BA/PPOMCs systems such as fracture toughness, dynamic mechanical property, dielectric property, and self‐healing ability were discussed. The morphologies of the cured resin systems were characterized using scanning electronic microscope and light microscopy. Results reveal that the addition of PPOMCs can catalyze the polymerization reaction of BDM/BA resins. BDM/BA systems with appropriate PPOMCs content cured at low temperature possess excellent fracture toughness, high glass transition temperature (T_g), and low dielectric property. The self‐healing ability of BDM/BA can be realized by the introduction of PPOMCs owing to the polymerization of the released core materials from PPOMCs. The self‐healing efficiency of healed BDM/BA/PPOMCs systems can be influenced by the size and content of PPOMCs and the contact areas between the crack surfaces. © 2013 Society of Plastics Engineers     

Properties and origins of high‐performance poly(phenylene oxide)/cyanate ester resins for high‐frequency copper‐clad laminates

A high‐performance matrix is the key base for the fabrication of high‐frequency copper‐clad laminates. A high‐performance resin system based on commercial poly(phenylene oxide) (PPO) and 2,2′‐bis(4‐cyanatophenyl) isopropylidene (BADCy), coded as PPO‐n/BADCy (where n is the weight parts of PPO per 100 weight parts of BADCy), was developed. The effect of PPO on the key properties, including the dielectric and thermal properties, water resistance, and toughness, of the cured resins was investigated extensively. The results show that PPO not only catalyzed the curing reaction of BADCy but also reacted with BADCy to form a single‐phase structure. Furthermore, compared with the cured BADCy resin with 1 phr epoxy resin as a catalyst, the cured PPO‐n/BADCy resins had significantly increased impact strengths and decreased dielectric constants, loss, and water resistance. The reasons behind these desirable improvements are discussed from the view of structure–property relationships. These results suggest that the PPO‐n/BADCy system has great potential to be used as a matrix for high‐frequency copper‐clad laminates or other advanced composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Allylated novolac/4,4′‐bismaleimidodiphenylmethane resin containing polyhedral oligomeric silsesquioxane: Preparation,morphology and thermal stability

Allylated novolac/4,4′‐bismaleimidodiphenylmethane resin (AN/BDM) had been modified with well‐defined inorganic building blocks‐polyhedral oligomeric silsesquioxane (POSS). Octamaleimidophenyl polyhedral silsesquioxane (OMPS) was used as the cocuring reagent of the AN/BDM resin to prepare POSS‐modified AN/BDM resin, and POSS content was between 0 and 17.8 wt %. The curing reaction of the POSS‐modified AN/BDM resin was monitored by means of Fourier transform infrared spectroscopy (FTIR), and the results revealed that maleimide groups on OMPS molecule could undergothe curing reaction between allyl groups and maleimide groups. Therefore, the crosslinked network containing POSS was formed. Scanning electron microscopy (SEM) and X‐ray diffraction (XRD) were employed to study the morphology of the cured POSS‐modified AN/BDM resins. The homogeneous dispersion of POSS cages in AN/BDM matrices was evidenced. Thermogravimetric analysis (TGA) indicated that incorporation of POSS into AN/BDM crosslinked network led to enhanced thermal stability. The improved thermal stability could be ascribed to higher crosslink density and inorganic nature of POSS. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 3903–3908, 2007     

Preparation and properties of addition curable silicone resins with excellent dielectric properties and thermal resistance

A new addition curable silicone resin (ASiR) system with excellent dielectric and thermal properties was developed, which consists of only two components: poly(methylphenylvinylsiloxane) (PMPVSi) and an end‐capped hydrogen‐functionalized hyperbranched polysiloxane (EHFHPSi). PMPVSi is synthesized by a green and controllable process; EHFHPSi is first synthesized via A₂ + B₃ approach, and then end‐capped by hexamethyldisiloxane (HMDS). Three formulations were designed to investigate the optimum stoichiometry. Results show that cured ASiR resins have greatly different dielectric and thermal properties because of the different chemical structure of cured networks resulting from the different stoichiometries. The resin with a suitable stoichiometry has not only excellent dielectric properties including extremely low dielectric constant (2.96 at 1 Hz) and loss (0.0003 at 1 Hz) as well as good stability on frequency, but also outstanding thermal resistance, exhibiting great potential to be used as a new kind of high‐performance resins for many cutting‐edge industries, especially the microelectronic and insulation fields. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers     

Synthesis of bismaleimide resin containing the poly(ethylene glycol) side chain: Curing behavior and thermal properties

Two maleimido end‐capped poly(ethylene glycol) (m‐PEG) of different molecular weights were synthesized and blended at various proportions with bismaleimide resin (4,4′‐bismaleimido diphenylmethane) (BDM). The curing behavior and the thermal properties of the m‐PEG/BDM blends were studied and presented here. It was found that the addition of m‐PEG enhanced the processability of the BDM resin significantly. The processing window of the BDM resin was increased from approximately 20 to 80°C. The addition of m‐PEG modified resins, however, resulted not only in the reduction in the thermal stability of the blended BDM resin but also elevation of the coefficients of thermal expansion. The changes in thermal/mechanical properties of the blends were found to be proportional to the amounts of m‐PEG incorporated. It was observed that the curing behavior, and thermal and mechanical properties, of the blends were independent of the molecular weight of the PEG segment. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2935–2945, 2002     

Curing behavior study of polydimethylsiloxane‐modified allylated novolac/4,4′‐bismaleimidodiphenylmethane resin

The curing behavior of polydimethylsiloxane‐modified allylated novolac/4,4′‐bismaleimidodiphenylmethane resin (PDMS‐modified AN/BDM) was investigated by using Fourier transform infrared spectrometry (FTIR) and differential scanning calorimetry. The results of FTIR confirmed that the curing reactions of the PDMS‐modified AN/BDM resins, including “Ene” reaction and Diels–Alder reaction between allyl groups and maleimide groups, should be similar to those of the parent allylated novolac/4,4′‐bismaleimidodiphenylmethane (AN/BDM) resin. The results of dynamic DSC showed that the total curing enthalpy of the PDMS‐modified AN/BDM resins was lower than that of the parent resin. Incorporation of polydimethylsiloxane (PDMS) into the backbone of the allylated novolac (AN) resin favored the Claisen rearrangement reaction of allyl groups. The isothermal DSC method was used to study the kinetics of the curing process. The experimental data for the parent AN/BDM resin and the PDMS‐modified AN/BDM resins exhibited an nth‐order behavior. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Modification of three‐component bismaleimide resin by poly(phthaloyl diphenyl ether) and related copolymers

A three‐component bismaleimide resin, composed of 4,4′‐bismaleimidodiphenyl methane (BDM), o,o′‐diallyl bisphenol A (DBA), and o,o′‐dimethallyl bisphenol A (1.0/0.3/0.7 eq ratio) was used as a parent bismaleimide resin. Modification of the three‐component bismaleimide resin was examined by blending it with poly(ether ketone ketone)s. Poly(ether ketone ketone)s include poly(phthaloyl diphenyl ether) (PPDE), poly(phthaloyl diphenyl ether‐co‐isophthaloyl diphenyl ether) (PPIDE), and poly(phthaloyl diphenyl ether‐co‐terephthaloyl diphenyl ether) (PPTDE). The PPIDE (51 mol % isophthaloyl) and PPTDE (44 mol % terephthaloyl) were more effective as modifiers for the bismaleimide resin than was PPDE. For example, the fracture toughness (K_IC) for the modified resin increased 30% with no deterioration in the flexural strength and modulus with a 15 wt % inclusion of PPTDE (MW 23,400) compared to the parent three‐component bismaleimide resin: the K_IC increased 95% compared to the value for the Matrimid 5292 resin composed of BDM and DBA. The morphologies of the modified resins changed from particulate to cocontinuous phase structures, depending on the modifier structure and concentration. Toughening of the cured bismaleimide resin could be achieved because of the cocontinuous phase structure. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2991–3000, 2001     

Fluorinated bismaleimide resin with good processability,high toughness,and outstanding dielectric properties

In this study, novel fluorinated bismaleimide (BMI) resins were prepared by the copolymerization of 2,2′‐bis[4‐(4‐maleimidephenoxy)phenyl]hexafluoropropane (6FBMP) and diallyl hexafluorobisphenol A (6FDABPA) to enhance their dielectric properties. The dielectric properties of the resins were investigated in the frequency range 7–18 GHz through a cavity method. Through the incorporation of a hexafluoroisopropyl group with the polymer chain, the dielectric constant (ε) was effectively decreased because of the small dipole and the low polarizability of the carbon‐fluorine (C? F) bonds. The 6FBMP/6FDABPA resin possessed excellent dielectric properties, with ε being 2.88 and the dielectric loss being 0.009 at 10 GHz and 25°C. In comparison with the 4,4′‐bismaleimidodiphenylmethane (BDM)/2,2′‐diallyl bisphenol A (DABPA) resin, the glass‐transition temperature (T_g) of 6FBMP/6FDABPA decreased. The flexible ether group in the long chain of 6FBMP was considered to disrupt chain packing and cause a decreased crosslinking density and a lower T_g. 6FBMP/6FDABPA showed a similar thermal decomposition temperature and good thermal properties like the BDM/DABPA resin, whereas the impact strength of the 6FBMP/6FDABPA resin was almost 1.6 times higher than that of the BDM/DABPA resin. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42791.     

Preparation and properties of high‐performance polysilsesquioxanes/bismaleimide‐triazine hybrids

A novel kind of high‐performance hybrids (coded as POSS‐NH₂/BT) with significantly decreased curing temperature, lowered dielectric constant and loss, and improved thermal resistance were developed, which were prepared by copolymerizing bismaleimide with cage octa(aminopropylsilsesquioxane) (POSS‐NH₂) to produce POSS‐containing maleimide, and then co‐reacted with 2,2′‐bis(4‐cyanatophenyl) isopropylidene. The curing behavior and typical properties of cured POSS‐NH₂/BT were systematically investigated. Results show that POSS‐NH₂/BT hybrids have lower curing temperatures than BT resin because of the additional reactions between  OCN and amine groups. Compared with BT resin, all hybrids show improved dielectric properties. Specifically, hybrids have slightly decreased dielectric constants and similar dependence of dielectric constant on frequency over the whole frequency from 10 to 10⁶ Hz; more interestingly, the dielectric loss of hybrids is only 25% of that of BT resin at the frequency lower than 10⁵ Hz, whereas all hybrids and BT resin have almost equal dielectric loss when the frequency is higher than 10⁵ Hz. In addition, POSS‐NH₂/BT hybrids also show good thermal and thermo‐oxidative stability compared with BT resin. All these differences in macroproperties are attributed to the difference in chemical structure between POSS‐NH₂/BT hybrids and BT resin. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Thermal and dielectric properties of bismaleimide‐triazine resins containing octa(maleimidophenyl)silsesquioxane

Octa(maleimidophenyl)silsesquioxane (OMPS) was synthesized, characterized, and employed to modify the BT resin which composed of 4,4′‐bismaleimidodiphenylmethane (BMI) and 2,2′‐bis(4‐cyanatophenyl)propane (BCE). The curing reaction between OMPS and BT resin was first investigated. It was found that OMPS accelerate the curing reaction of BCE, and the onset temperature of the cyclotrimerization was reduced up to 95.5°C (by DSC). As demonstrated by DSC and FTIR, there was no evidence that indicated the coreaction between maleimide and cyanate ester. 2,2′‐diallyl bisphenol A (DBA) and diglycidyl ether of bisphenol A (E‐51) (Wuxi Resin Factory, Jiangsu Province, China) were also used to enhance the toughness of BT resin, and the formulated BTA (containing DBA) and BTE (containing E‐51) resins were obtained. The thermal properties of BT, BTA, and BTE resins incorporated with OMPS were then investigated. The results of DMA and TG showed that the BT, BTA, and BTE resins containing 1 wt % of OMPS exhibit enhanced thermal properties in comparison with their pristine resins respectively, while more contents of OMPS may impair the thermal properties of the polymer matrix, though the effect of OMPS was slight. Finally, the dielectric constant of these hybrid materials were detected, and their dielectric constant were distinctly reduced by the incorporation of OMPS, while overmuch contents of OMPS were disadvantageous for dielectric constant because of the aggregation of OMPS. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Mechanical,thermal and dielectric properties of BDM/DBA/HBPSi composites

N, N′-4, 4′-bimaleimide diphenyl methane (BDM), diallylbisphenol A (DBA) and hyperbranched polysiloxane (HBPsi) are performed to fabricate the BDM/DBA/HBPSi composites by one-step method. The contents of HBPSi affecting on the mechanical, thermal and dielectric properties of the BDM/DBA/HBPSi composites are investigated. Results show that the appropriate incorporation of HBPSi into BDM/DBA not only significantly improves the toughness, but also improves the heat resistance and dielectric properties of the BDM/DBA/HBPSi composites. The outstanding comprehensive properties of BDM/DBA/HBPSi composites indicate great potentiality in fabricating advanced polymeric composites.     

Modification of two-component bismaleimide resin by blending (meth)allyl compounds as third components

A two-component bismaleimide resin composed of 4,4′-bismaleimidediphenyl methane (BDM) and o,o′-diallyl bisphenol A (DBA) (Matrimid 5292 resin) was used as a parent bismaleimide resin. Modification of the parent bismaleimide resin was examined using several kinds of (meth)allyl compounds as the third component. The (meth)allyl compounds include triallyl isocyanurate (TAIC), o,o′-dimethallyl bisphenol A (DMBA) and trimethallyl isocyanurate (TMAIC). In the ternary BDM/DBA/TAIC blends, the fracture toughness K_IC and flexural strength for the cured resins decreased with increasing TAIC content; thermal properties of the cured resins were not deteriorated. In the ternary BDM/DBA/DMBA blends, K_IC and flexural modulus for the cured resins increased and their glass transition temperatures decreased with an increase in DMBA content. Flexural strength increased up to DMBA 70 eq% blend and then decreased. In the ternary blend of BDM/DBA/TMAIC (1.0/0.5/0.5), K_IC for the blend increased 15%, with retention of flexural property and T_g. In the ternary BDM/DMBA/TMAIC (1.0/0.5/0.5) blend, the cured resin had balanced properties and its K_IC increased 50% compared to the cured Matrimid resin. © 1999 Society of Chemical Industry     

Preparation and characterization of soluble bismaleimide‐triazine resins based on asymmetric bismaleimide

A series of bismaleimide‐triazine resins (EBT) were prepared from 2‐(4′‐maleimido)phenyl‐2‐(4′‐maleimidophenoxyl)phenylbutane (EBA‐BMI) and 2,2‐bis(4‐cyanatophenyl)propane (BADCy). The resins show attractive processability with good solubility in low boiling point solvents and wide processing temperature windows. Introduction of diallylbisphenol A (DBA) can decrease the curing temperature of EBT resins that the curing exothermic peak temperature shifted from 291 to 237 °C as the content of DBA increased from 0 to 20%. The curing condition influenced the thermal properties of the cured EBT resins. The glass transition temperature increased as the curing temperature and curing time increased. The cured EBT resins show high glass transition temperature up to 352 °C, high thermal stability with 5% weight loss temperature over 405 °C, low coefficient of thermal expansion about 45 to 52 ppm/°C, and high storage modulus up to 2.6 GPa at 250 °C. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44519.     

Preparation,curing properties,and phase morphology of epoxy‐novolac resin/multiepoxy‐terminated low‐molecular‐weight poly(phenylene oxide) blend

The multiepoxy‐terminated low‐molecular‐weight poly (phenylene oxide) (PPOE) was synthesized by modifying the terminal hydroxyl group of poly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) with epoxy‐novolac resin (EPN). The curing kinetics, phase morphology, and thermal stability of the cured EPN/PPOE blends were investigated and compared to the unmodified EPN/PPO and EPN/EPPO (epichlorohydrin‐modified PPO) blends. As revealed by the Fourier transform infrared and differential scanning calorimetry analyses, PPOE took part in the curing reaction and formed a crosslinked structure with EPN. The curing rate of EPN/PPOE blends first increased and then decreased with the increase of PPOE fraction. PPOE had both catalytic and steric hindrance effects on the curing reaction. EPN/PPOE blends showed faster curing rate and higher degree of curing than the corresponding EPN/PPO and EPN/EPPO blends. The reactive blending improved the dispersion of PPOE in EPN matrix and the thermal stability of the blend. POLYM. ENG. SCI., 54:2595–2604, 2014. © 2013 Society of Plastics Engineers     

A simple imide compound as a curing agent for epoxy resin. I. Synthesis and properties

A simple imide compound, 4‐amino‐phthalimide (APH), was synthesized as a curing agent for epoxy resin. APH was prepared from the hydration of 4‐nitro‐phthalimide, which was prepared from the nitration of phthalimide. The chemical structure of APH was verified by IR and ¹H‐NMR spectra. The thermal properties and dielectric constant (ε) of a phosphorus‐containing novolac epoxy resin cured by APH were determined and compared with those of epoxy resins cured by either 4,4′‐diamino diphenyl methane (DDM) or 4,4′‐diamino diphenyl sulfone (DDS). The results indicate that the epoxy resin cured by APH showed better thermal stability and a lower ε than the polymer cured by either DDM or DDS. This was due to the introduction of the imide group of APH into the polymer structure. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Preparation of β‐SiCw/BDM/DBA composites with excellent comprehensive properties

Functionalized β‐SiC whiskers (β‐SiCw) are employed to prepare β‐SiCw/N,N′‐4, 4′‐bimaleimide diphenyl methane/diallylbisphenol A (β‐SiCw/BDM/DBA) composites via powder blending‐casting method. The thermal conductive coefficient of the β‐SiCw/BDM/DBA composites is 0.994 W/mK with 40 wt% functionalized β‐SiCw, five times higher than that of pure BDM/DBA. The mechanical properties of the β‐SiCw/BDM/DBA composites are optimal with 10 wt% functionalized β‐SiCw. Both thermal resistance and dielectric constant are increased with the increasing addition of β‐SiCw. For a given β‐SiCw loading, the surface functionalization of β‐SiCw exhibits a positive effect on the thermal conductivities and mechanical properties of the β‐SiCw/BDM/DBA composites. POLYM. COMPOS., 35:1875–1878, 2014. © 2014 Society of Plastics Engineers     

Materials containing benzocyclobutene units with low dielectric constant and good thermostability prepared from star-shaped molecules

With the development of ultralarge-scale integrated circuits, polymers with low dielectric constant and high thermal stability have aroused great interest. We prepared two novel bridged siloxane-based benzocyclobutene (BCB) star-shaped monomers, tetrakis[dimethyl siloxy-4-(1′,1′-dimethyl-1′-ethyl silicon)-benzocyclobutene] (TDSDES-BCB) and tetrakis(hexamethyl siloxane vinyl-benzocyclobutene) (THSV-BCB), and the corresponding resins were obtained by curing. The structures of TDSDES-BCB and THSV-BCB were confirmed by ¹H-NMR, ¹³C-NMR, and ²⁹Si-NMR spectra and time-of-flight mass spectrometry analysis. The curing behavior of these monomers was investigated by Fourier transform infrared spectroscopy and differential scanning calorimetry. The dielectric constant of cured TDSDES-BCB is only 2.43 at 10 MHz (that of THSV-BCB is 2.46). In addition, these resins display high thermal stability: the 5 wt % weight loss temperature of cured TDSDES-BCB is about 467 °C (454 °C for THSV-BCB resin). The excellent low dielectric property is attributable to the free volume created by the star-shaped structure and crosslinked network structure of BCB after curing. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47458.