Surface Of PBO Fibers Research Articles

Improving UV aging resistance by loading PDA on the surface of PBO fibers via Fe (III) coordination

Poly(p-phenylene-2,6-benzobisoxazole) (PBO) fiber is currently one of the best-performing organic fibers; however, its low UV aging resistance limits its use. To improve the UV aging performance of PBO fibers, a novel PBO-Fe-PDA fiber was created by depositing a biomimetic structure of polydopamine (PDA) on the surface of PBO fibers with the transition metal ion Fe3+ as the active center. The surface morphology and elemental composition of PBO-Fe-PDA fibers were investigated. It was revealed that Fe3+ formed a coordination bond structure with the oxazole ring, and PDA was successfully loaded onto the surface of PBO-Fe fibers. After UV aging, the crystallinity and crystallographic orientation of PBO fibers significantly decrease, microcrystals inside the fibers slip, and the size of microvoids in the fibers rises. As a result, the strength of PBO fibers was significantly decreased after UV aging. The anti-UV aging capacity of PBO-Fe-PDA fibers, on the other hand, has been enhanced, as evidenced by a slight drop in crystallinity and crystallographic orientation and a significant decrease in the size growth of internal microvoids in the fibers after UV aging. The tensile strength retention of PBO-Fe-PDA fibers after UV aging increased by 93.13% when compared to PBO fibers without altering the fibers’ initial strength. The testing results show that this surface modification method is simple to employ and extends the service life of PBO fibers significantly.

Significantly improved interfacial properties of silicon dioxide nanowire functionalized poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers/polytetrafluoroethylene (PTFE) wave-transparent laminated composites

Poly(p-phenylene-2,6-benzobisoxazole) (PBO) fiber and polytetrafluoroethylene (PTFE) resin have been widely acknowledged as excellent wave-transparent materials for future high-frequency applications due to their exceptional dielectric properties. However, the weak interfacial bonding between these two materials hampers their full potential. In this study, we successfully addressed this limitation by enhancing the surface roughness of PBO fibers and introducing active sites through the in-situ grafting of silica nanowires. The added silica acted as an interfacial anchor on the PBO fiber surface, significantly improving the bonding force between PBO and PTFE. PBO/PTFE wave-transparent laminated composites were fabricated using hot compression molding. The results demonstrate that the PBO (treated with in-situ grown silica)/PTFE laminated composites exhibit superior interlaminar shear strength (ILSS), flexural strength, flexural modulus, and tensile modulus compared to the pristine PBO/PTFE laminated composites. Specifically, these properties are found to be 58.6%, 32.9%, 138.1%, and 25.35% higher, respectively. Additionally, these composites demonstrate low dielectric constant and dielectric loss. Most notably, they achieve a wave transmittance of 91.45% at 10 GHz, indicating significant potential for wide-range applications in next-generation advanced military weapons, such as “lightweight/high-strength/wave-transparent” electromagnetic window materials, as well as civilian communication base stations.

Synergistically enhanced interfacial and wave-transparent properties of PBO fiber composites: Constructing self-assembly interphase with different dimensional COF

Naphthalimide-linked covalent organic framework (COF) with two-dimensional (A-COF and B–COF) and three-dimensional structure (M-COF) was designed and applied to self-assembly on PBO fiber surface, and the influences of 2D or 3D COF on interfacial and wave-transparent properties as well as their reinforcing mechanisms of composites were investigated. A-COF and M-COF exhibited higher BET surface area and porosity compared to those of B–COF, and the morphology of 2D and 3D COF respectively presented lamellar nanosheet and random particle aggregation. The dense inner COF layer and numerous nanocrystals were attached on 2D COF@PBO fiber, and 3D COF@PBO fiber surface showed nano-porous structures from M-COF nanoparticle stacking. Compared with pristine PBO fiber composites, transverse fiber bundle tensile (TFBT) strength and interfacial shear strength (IFSS) of A-COF@PBO and B–COF@PBO fiber composites were increased by 38.76% and 51.77%, 37.23% and 43.94% due to lamellar stacking structure of 2D COF, while 15.31% and 19.56% increment for M-COF@PBO fiber composites, which was attributed to the weaker binding force between PBO fiber and 3D COF from interpenetrated structure. The optimal wave transmission efficiency (|T|2) at low frequency was obtained for A-COF@PBO fiber composites, resulting from the highest porosity of A-COF and best interfacial compatibility, while M-COF@PBO fiber composites showed the best |T|2 at high frequency due to the higher porosity and scarce electron-coupling phenomenon of M-COF.

Grafting of CNTs onto the surface of PBO fibers at high-density for enhancing interfacial adhesion, mechanical properties and stability of composites

To improve the interfacial adhesion and mechanical performance of PBO fiber composites, CNTs were uniformly grafted onto them at a high-density. The grafting of CNTs with massive reactive groups can improve the surface wettability and interfacial interaction of PBO fibers with epoxy resin. The IFSS and ILSS values of themodified composites (PBO-CNT-3) increased by 103.09 and 62.73%, respectively. As CNTs can strengthen interfacial regions of the composites, the mechanical properties (hardness and modulus) of the interphase were enhanced significantly. This led to the effective transfer of interfacial load, elimination of stress concentration, and improvement in the structural stability of the composites. As a result, the impact strength of the modified composites (PBO-CNT-3) was up to 103.76 kJ/m2 (an increase of 56.24%) compared to the original composites. The surface morphology and deformation behavior of the fractured composites indicate that the interfacial failure mode of the composites grafted with CNTs changes from adhesive failure to both cohesive and substrate failure. This strategy of grafting CNTs at a high-density opens a new avenue for the interfacial regulation of structural composites, ultra-capacitor, sensor, and catalytic materials.

The effect of different grafting extent of PBO‐MoS2 hybrids on the tribological performance of TPI‐based composites at high temperatures

AbstractThe self‐assembled hybrids were synthesized as a kind of filler with the function of reinforcing and lubricating, by which can improve its dispersion in the matrix, and enhance the interfacial adhesion with the matrix. However, the effect of the amount of grafting on the hybrid properties is still unclear. In this study, a series of antiwear hybrids with different grafting amount were synthesized and further be used to reinforce thermoplastic polyimide matrix. The method of comparative analysis had been applied to analyze the microstructural morphology, thermal property, mechanical property, and high temperature tribological behavior of these composites. The results indicated that with the increasing grafting amount of MoS2 on the PBO fiber surface in a certain range, the integrated performance of the composite increases.

Surface modification of PBO fibers with 2,2-Bis (3-amino-4-hydroxyphenyl) hexafluoropropane in supercritical carbon dioxide for enhancing interfacial strength

PBO fiber is one of the most promising reinforcements in resin matrix composite because of its excellent mechanical properties. However, the inert and smooth surfaces make it the poor interface adhesion with resin matrix, which seriously limits the application in composites. In this article, we report a method to modify the surface of PBO fibers with 2,2-Bis (3-amino-4-hydroxyphenyl) hexafluoropropane（BisAPAF）in supercritical CO2 to enhance interfacial properties. Chemical structures, surface elemental composition and functional groups, and surface morphology were characterized by FT-IR spectrometer, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM), respectively. The mechanical properties of the samples were tested by a tensile tester. Static contact angle and microdebonding tests were used to characterize the wetting ability and interfacial shear strength (IFSS) of the fiber and epoxy resin. The results showed that the BisAPAF could be solved in scCO2 and introduced more groups, –NH2, –OH, and –CF3 on the fiber surface, resulting in the mechanical properties and the wettability of PBO fiber slightly improved. Moreover, the fiber surface roughness was also increased obviously. The IFSS between the modified PBO fiber and epoxy resin increased from 8.18 MPa to 31.4 MPa when the treating pressure was 14 MPa. In general, the method to modify PBO fibers surface using BisAPAF in scCO2 can effectively improve their interfacial properties.

Facile immobilization of graphene nanosheets onto PBO fibers via MOF-mediated coagulation strategy: Multifunctional interface with self-healing and ultraviolet-resistance performance

The surface of poly (p-phenylene benzobisoxazole) (PBO) fibers with self-healing and ultraviolet (UV)-resistance performance play the key role in prolonging their service lifespan. Although great advances have been made in the single aspect of above two properties, integration of self-healing and anti-UV performance into the surface of PBO fiber is still a challenge. In this study, the coagulation strategy mediated by metal-organic framework (MOF) is proposed to construct the multifunctional surface of PBO fibers. The spindle-like iron (III)-based MOF (MIL-88B-NH2) nanocrystals are firstly immobilized onto the surface of PBO-COOH through hydrothermal reaction, then serving as the medium layer to further immobilize sufficient graphene oxide (GO) nanosheets. Benefitting from the favorable near-infrared (NIR, 808 nm) photothermal conversion performance of GO nanolayers, the monofilament composite-PBO@Fe-MIL-88B-NH2-GO-TPU (thermoplastic polyurethane) exhibited a stable and high self-healing efficiency (approximately 80%) within five cycle times. Meanwhile, the cooperative adsorption and shielding weaken effects of MOF-GO nanolayers enabled PBO fibers with excellent anti-UV properties that are superior to much reported literatures after 96 h aging time and eventually increased by 75% compared with untreated PBO fiber. In view of the varieties and multifunctionalities of MOFs and carbon nanomaterials, MOF-mediated coagulation strategy would provide guidance for preparing multifunctional composite materials.

Layer-by-layer constructing interface with rigid-flexible transition structure for improving interfacial adhesion of PBO fiber composites

Constructing interface with customized structures of fiber composites is an effective method of achieving high performance. Herein, the comb-like polymer interface with a rigid-flexibility transition structure was constructed on the PBO fiber surface through the layer-by-layer (LBL) method. Compared with original PBO fiber composites, the interfacial adhesion and stability of interface structures were improved significantly due to the LBL construction of comb-like polymers interface. In modified fiber (PBO–P3) composites, the IFSS and ILSS value were increased by 76.30 and 39.31%, respectively. Meanwhile, dynamic mechanical properties and hydrothermal aging resistance were also enhanced obviously. The main contributors for improved interfacial adhesion could be the enlarged interface region with rigid-flexible transition structure, complicated interface contact, enhanced chemical bonding and mechanical interlocking near interface area.

Evaluation of the alkali and oxidation resistance of PBO fibers

Poly( p-phenylene benzobisoxazole) (PBO) fiber, well-known for its super high strength, is a novel fiber with excellent heat resistance and flame retardancy. However, chemical stability appears to be one of its few weaknesses. In this study, PBO fibers were treated with sodium hydroxide (NaOH) and potassium permanganate (KMnO4) solutions under various conditions. Scanning electron microscopy, optical microscopy, tensile testing, Fourier-transform infrared spectroscopy, differential scanning calorimetry (DSC), and thermogravimetric analysis were employed to characterize the variations of its structure and properties. The results show that many longitudinal corrosion grooves appeared on the surface of PBO fibers treated with KMnO4, while only subtle microcracks occurred after treatment with NaOH. The breaking tenacity of the fiber decreased from 38.13 cN dtex−1 to 2.76 cN dtex−1 after treatment with KMnO4 for 6 h, while it remained at a higher level (27.67cN dtex−1) when treated with NaOH. After treatment with KMnO4 solution, a more obvious absorption peak appeared in the vicinity of 1448.3 cm−1, inferring an occurrence of chemical changes for oxazole ring. Moreover, the remaining mass and initial degradation temperature are significantly improved, also indicating that the cyclic or cross-linked structure is rebuilt. Furthermore, the cyclization or cross-linking of macromolecules destroyed the highly ordered structure of PBO fibers, demonstrated by acromion melting peaks at low temperature in the DSC curves. However, the aggregation and chemical structures of PBO fibers have no obvious changes after treatment with NaOH.

Random copolymer membrane coated PBO fibers with significantly improved interfacial adhesion for PBO fibers/cyanate ester composites

Poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers possess excellent dielectric, mechanical properties and heat resistance. However, the surface of PBO fibers is smooth and highly chemical inert, resulting in poor interfacial compatibility to polymer matrix, which severely limits its wider application in high-performance fiber-reinforced resin matrix composites. In this work, random copolymers (P(S-co-BCB-co-MMA)) containing benzocyclobutene in the side-chain were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization, which were then utilized to form dense random copolymer membrane on the surface of PBO fibers by thermally cross-linking at 250 °C (PBO@P fibers). Four kinds of synthesized P(S-co-BCB-co-MMA) with different number-average molar mass (Mn) were well controlled and possessed narrow dispersity. When the Mn was 32300, the surface roughness of PBO@P fibers was increased from 11 nm (PBO fibers) to 39 nm. In addition, PBO@P fibers presented the optimal interfacial compatibility with bisphenol A cyanate (BADCy) resins. And the single fiber pull-out strength of PBO@P fibers/BADCy micro-composites was 4.5 MPa, increasing by 45.2% in comparison with that of PBO fibers/BADCy micro-composites (3.1 MPa). Meantime, PBO@P fibers still retained excellent tensile strength (about 5.1 GPa). Overall, this work illustrates a simple and efficient surface functionalization method, which would provide a strong theoretical basis and technical support for controlling the surface structure & chemistry of inert substrates.

Improved wave-transparent performances and enhanced mechanical properties for fluoride-containing PBO precursor modified cyanate ester resins and their PBO fibers/cyanate ester composites

Poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers can be applied as reinforcement to fabricate PBO/cyanate ester (CE) resin laminated composites with light weight, high specific strength & modulus, excellent dielectric properties, and extraordinary excellent thermal & humidity resistance for radome application. However, the surface of PBO fibers is extremely inert, resulting in poor interfacial compatibility to CE matrix. Besides, the toughness and wave-transparent performances of the cured CE resins need to be further improved. In this work, 2, 2-bis(3-amino-4-hydroxyphenyl) hexafluoropropane (6FAP) and terephthaloyl chloride (TPC) were performed to synthesize fluorine-containing epoxy-terminated PBO precursor (epoxy-preFPBO) via condensation reaction followed by end-group functionalization with glycidol. Afterwards, epoxy-preFPBO modified CE resins (FPBO-co-BADCy resins) were prepared by copolymerization of epoxy-preFPBO and bisphenol A cyanate ester (BADCy). FPBO-co-BADCy resins with 7 wt% epoxy-preFPBO displayed the optimal wave-transparent performances and mechanical properties. Dielectric constant (ε) and dielectric loss (tanδ) is respectively 2.48 and 0.0081, and the corresponding transmittance (|T|2) at 10 MHz is 94.9%, higher than that of pure BADCy (92.7%). The corresponding flexural and impact strength was enhanced to 119.9 MPa and 12.3 kJ/m2, 21.4% and 24.5% higher than that of pure BADCy, respectively. In addition, FPBO-co-BADCy resins presented better interfacial bonding strength with PBO fibers than that of pure BADCy.

A facile method for crystallizing flower-like CuS on the surface of PBO fiber

Abstract This study provided a manageable method to induce 3D flower-like CuS to crystallize on the surface of Poly(p-phenylenebenzobisoxazole) fiber (PBO fiber) by loading transition metal Pd by hydrothermal method. Pd as the induction center was attached to the surface of the acidified PBO fiber by the process of “sensitization” and “activation”. And then during hydrothermal synthesis, under the condition of transition metal Pd, CuS seeds are formed on the surface of PBO fiber, and these seeds proceed to grow. Finally, the flower-like CuS was successfully grown on the surface of PBO fiber. Scanning electron microscope, X-ray diffraction analysis, Energy dispersive spectrometer were used to confirm the growth process of CUS on the surface of PBO fiber.

Surface modification of PBO fiber by grafting nanoporous SiO2 coating with improved interfacial properties

PBO fiber has been valued for its excellent mechanical properties and is generally used as a reinforcement for resin-based fiber. However, as a result of its surface inertness, the degree of bonding of the PBO fiber between the resin is very low. The fibers in composites are easily pulled out, and their performance often falls short of expectations. Therefore, researching on the surface improvement of PBO fiber is essential. In this paper, silica coating with a nano-porous structure was grafted on the surface of PBO fiber by sol-gel method, using 3-glycidoxypropyltrimethoxysilane (GPTMS) as a silane coupling agent, and ethyl orthosilicate (TEOS) as silicon source. The PBO and modified PBO were characterized by Fourier transform infrared spectrum (FTIR), scanning electron microscopy(SEM), Energy dispersive spectrometer (EDS), Single-fiber microdroplet pull-out testing, Brunauer–Emmett–Teller (BET) characterization, tensile test and wettability test. The result showed that PBO/SiO2 fiber not only had good mechanical properties, but also owned superhydrophobic property. And it also revealed that the IFSS value of PBO/SiO2 fiber between epoxy resin was enhanced by 114.8% in the interfacial shear strength test. The importance and originality of this study is that it explores an efficient way to improve the adhesiveness between PBO fiber with resin.

Enhancement of hydrophobicity and UV aging resistance of Poly (p-phenylene benzobisoxazole) fibers modified by fluorosilane and UV absorber

Poly (p-phenylene benzobisoxazole) (PBO) fibers were functionalized by 3-Glycidoxypropyltrimethoxysilane (KH-560) and then coated with 1 H, 1 H, 2 H, 2H-Perfluorodecyltrimethoxysilane (HFTES) and UV absorber (UV-328) to improve hydrophobicity and UV aging resistance. The chemical compositions of PBO fibers before and after modification were analyzed by XPS and surface morphologies were observed by SEM. The hydrophobicity of PBO fibers was evaluated by the measurement of contact angle for water and the UV aging resistance was evaluated by the tensile strength retention ratio of PBO fibers. The results showed that KH-560 was successfully introduced onto the PBO fiber surface. The contact angle for water was increased by 128% from 51.7° to 127°, suggesting a huge improvement of hydrophobicity. The UV aging resistance of PBO fibers was also greatly improved. After 400 h UV exposure, the tensile strength retention ratio was increased to 53%, which was much higher than that of 21.4% for pristine PBO fibers. And the results of variable coating times demonstrated that the optimal UV aging resistance was obtained by coating three times.

Flexible conductive copper/reduced graphene oxide coated PBO fibers modified with poly(dopamine)

Nowadays, flexible fiber heater has attracted great interests. Here, we fabricated a copper/reduced graphene oxide (Cu/RGO) hybrids coating on the surface of poly(p-phenylene benzobisoxazole) (PBO) fiber with excellent tensile strength, high thermal stability and high flame retardancy for electrothermal heater. Copper was plated on the surface of PBO fibers by the modification of the PBO fibers with poly(dopamine) followed by RGO activation and electroless copper plating and copper coated PBO fibers (Cu/RGO-PBO) is obtained. Poly(dopamine) and RGO acted as synergistic activating agents for electroless copper plating. Cu/RGO-PBO fibers exhibit low electrical resistance of 0.16 Ω cm−1 and possess excellent electrical conductivity even after 20 cycles of washing. The heating temperature of Cu/RGO-PBO fibers is steady at around 44 °C which is suitable for keeping body warm. Additionally, Cu/RGO-PBO fibers reveal a low corrosion current density of 2.46 μA cm−2. The result indicates flexible Cu/RGO-PBO fibers with excellent electrical conductivity, heating performance and corrosion resistance, which could be used as flexible electrically conductive fiber and wearable heater with corrosion resistance.

Flexible reduced graphene oxide/electroless copper plated poly(benzo)-benzimidazole fibers with electrical conductivity and corrosion resistance

In order to produce conductive poly(benzo)-benzimidazole (PBO) fibers with corrosive resistance, copper plating on the surface of PBO fibers was carried out via palladium-free activation by electroless plating, followed by partial reduced graphene oxide (rGO) coating via electrophoretic deposition (EPD). The morphology, element composition and crystal structure of copper plated PBO (Cu/PBO) fibers were studied by scanning electron microscopy with energy dispersive spectroscopy, X-ray photoelectron spectroscopy and X-ray diffraction, respectively. Effect of deposition time on the deposition rate of copper, deposit weight and electrical resistance of Cu/PBO fibers was investigated. In addition, electrical conductivity and heat generation of Cu/PBO fibers were evaluated. The surface of PBO fibers is uniformly and densely covered with spherical copper particles and Cu/PBO fibers possess excellent conductivity with the electrical resistance of 2.98 × 10−3 Ω m for deposition time of 70 min. The corrosion resistance of reduced graphene oxide coated copper plated PBO (rGO/Cu/PBO) fibers was studied by Tafel analysis. The corrosion potential has a negative shift of 31 mV (from − 240.2 to − 209.2 mV) and Icorr reduces from 4.34 µA/cm2 for Cu/PBO fibers to 1.24 µA/cm2 for the rGO/Cu/PBO fibers. The results indicate that the rGO coatings on Cu/PBO fibers can protect copper coating against corrosion. The results indicate that rGO/Cu/PBO fibers possess excellent electrical conductivity and corrosive-resistance, which could be used as conductive flexible materials with corrosive resistance.

Construction of Anti-Ultraviolet "Shielding Clothes" on Poly( p-phenylene benzobisoxazole) Fibers: Metal Organic Framework-Mediated Absorption Strategy.

A metal-organic framework (MOF)-mediated adsorption strategy is first developed for improving the anti-ultraviolet (UV) properties of poly( p-phenylene benzobisoxazole) (PBO) fibers. In this work, UIO-66 was successfully anchored onto the surface of PBO fibers by one-step microwave-assisted heating method. The experimental results showed an obviously enhanced surface energy (91.1%), roughness (268.4%), interfacial shear strength (49.0%), and anti-UV properties (66.7%) compared to pristine PBO fibers. The anti-UV dye (tartrazine) was further immobilized onto the surface of PBO fibers via an adsorption strategy mediated by UIO-66. Interestingly, the PBO@tartrazine fibers demonstrated superior anti-UV performance (further up to 81.5%) compared to PBO@UIO-66 fibers. The extraordinary anti-UV properties of PBO@tartrazine fibers could be rationally ascribed to the synergistic effects of UIO-66 and tartrazine molecules. Considering the diversities and functionalities of MOFs and targeted materials, our work indicates that the MOF-mediated adsorption strategy would promisingly endow PBO fibers with other desired performance and applications such as solar-thermal transition and self-healing abilities.

Fabrication and investigations on the polydopamine/KH-560 functionalized PBO fibers/cyanate ester wave-transparent composites

Abstract Functionalized poly (p-phenylene-2, 6-benzobisoxazole) (f-PBO) fibers were firstly obtained by introducing polydopamine (PDA) and 3-GlycidoxypropyltriMethoxysilane (KH-560), then performed to fabricate the f-PBO fibers/fluoride-containing bisphenol A dicyanate ester (m-BADCy) wave-transparent laminated composites. PDA was coated on the surface of PBO fibers and KH-560 was also grafted onto the PBO fibers. And the single fiber pull-out strength of the f-PBO fibers/m-BADCy micro-composites was increased from 3.2 MPa (PBO fibers/BADCy) to 4.0 MPa. Interlaminar shear strength (ILSS) and flexural strength of the f-PBO fibers/m-BADCy composites was also enhanced to 49.5 MPa and 652.2 MPa, increased by 39.8% and 12.1%, compared with that of PBO fibers/BADCy composites (ILSS of 35.4 MPa and flexural strength of 582.0 MPa), respectively. The corresponding e and tanδ was decreased to 2.86 and 5.7 × 10-3, declined by 6.5% and 23.0%, compared with that of PBO fibers/BADCy composites (e of 3.06 and tanδ of 7.4 × 10-3), respectively.

Preparation of PBO/ZnO fibers by hydrothermal synthesis method and its properties

In this article, zinc oxide (ZnO) nanoparticles were synthesized and deposited on the surface of PBO fibers through hydrothermal synthesis method. The structures and properties of PBO/ZnO fibers and PBO fibers were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), x-ray diffraction (XRD), Fourier transform infrared spectrum (FTIR), Thermogravimetric analysis (TG), and tensile testing. The results revealed that the PBO/ZnO fibers have good mechanical properties and high thermal stability. Moreover, the fibers exhibited excellent UV-blocking properties by putting them under UV irradiation of 313 nm. Specifically, ZnO coated fibers will lose only 18.93% of tensile strength after 50 h irradiation, and then will keep over 65% of tensile strength after 100 h UV irradiation. Additionally the interface shear strength is increased significantly, and the results also showed modified PBO fibers exhibited excellent hydrophobic quality. So the functional materials have great potentials in future engineering applications.

A facile method modified PBO fibers by polysiloxane microtube

We reported a room-temperature chemical vapor deposition (CVD) in which ethyltrichlorosilane was used as precursor to produce 1D micro-structures made from polysiloxane on PBO fibers surface. In this article, the reaction on the fibers’ surface increased via treatment with the plasma, and then the self-assembly of alkylsilane was used to form the polysiloxane microtubes on the surface of PBO fibers, and the growth rate of polysiloxane microtubes can be controlled by the moisture content, which is controlled by nitrogen. The modified PBO fibers can be obtained by various characterizations, which confirm that the surface of the fibers has silicon.