Γ-aminopropyl Triethoxysilane Research Articles

Preparation of hybrid nanofiltration membranes based on Schiff base reaction for hard water softening

To obtain positively charged layer and achieve high divalent cation rejection, a novel nanofiltration (NF) membrane was successfully fabricated by utilizing polyethyleneimine (PEI), newly fabricated polyacrolein (PA) and amine silane coupling agent γ-aminopropyl triethoxysilane (APTES). The PA was synthesized via radical polymerization to avoid the migration and volatilization of small molecule in the typical coating process, making NF membranes even with great stability. On the one hand, the PEI crosslinked with PA through Schiff base reaction; on the other hand, the in-situ hydrolysis self-polycondensation of APTES generated loose networks with Si-O-Si bonds which provided the permeation channel for water and accordingly boosted the water permeance. The water permeance of the optimal PEI/PA/APTES membrane could reach 16.9 L·m-2·h-1·bar-1 and the Mg2+ and Ca2+ rejections were 98.8% and 97.3%, respectively, better than those of commercial NF membranes, breaking up the “trade off” effect. This study prepared a high-performance PEI/PA/APTES hybrid NF membrane oriented for hard water softening in tap water and brackish water via the non-interfacial macromolecule crosslinking coating method.

A novel method to improve the anti-ageing ability of bitumen by organic LDHs/SBS composite: Preparation, performance evaluation and mechanism analysis

γ-aminopropyltriethoxy silane organic layered double hydroxides (LDHs) and SBS were combined into LDHs/SBS composite to improve anti-ageing performance of SBS modified bitumen (SMB). XPS and SEM showed that organic LDHs (OLDHs) was successfully grafted onto SBS, and OLDHs could be more evenly distributed in SBS, which was conducive to improve the anti-degradation capability of SBS. Compared with SBS and LDHs/SBS composite, the interaction between OLDHs/SBS composite and bitumen was stronger, resulting in the better stabilization of SBS and LDHs in bitumen. Furthermore, OLDHs/SBS composite could enhance the high-temperature property of SMB. SMB became hard and brittle during ageing, the physical and rheological properties were remarkably deteriorated. LDHs/SBS and OLDHs/SBS composite could alleviate the damage of ageing on the high- and low-temperature performance of SMB and enhance the anti-ageing capacity, particularly OLDHs/SBS composite. Then, the improvement mechanism of OLDHs/SBS and LDHs/SBS composite on the anti-ageing capability of SMB was analyzed at microscopic scale. LDHs/SBS and OLDHs/SBS composite could hinder the infiltration of oxygen into bitumen and decrease the oxygen content, and simultaneously decelerate the oxygen diffusion rate in bitumen. The synergistic combination of these two functions conspicuously diminished the probability of oxygen colliding with bitumen or SBS, which relieved the ageing of bitumen and the degradation of SBS, and ultimately improved the anti-ageing capability of SMB. Furthermore, due to the better stability, the effectiveness of OLDHs/SBS composite was more notable than LDHs/SBS composite, OLDHs/SBS composite demonstrated superior improvement on the anti-ageing capability of SMB than LDHs/SBS composite.

Preparation and characterization of self-dispersive and reactive carbon black and its application in cotton fabric

This study aims to develop a self-dispersive and reactive carbon black (DRCB) to improve its application in cotton fabric. CB was functionalized with γ-aminopropyl triethoxysilane (KH550) and then grafted with as-synthesized compound to obtain aqueous phase DRCB. FTIR analysis confirmed the successful grafting of as-synthesized compound onto KH550-modified CB surface. The weight grafting of DRCB on DRCB-15 % dyed cotton fabric was approximately 15.18 %, with a half weight grafting time of around 17 min. TEM observation demonstrated that DRCB had a core-shell structure with the mean sizes of 36.02 ± 4.30 nm. Particle size analysis revealed that DRCB had smaller average aggregate size of 110.3 nm and higher zeta potential of −33.7 mV than CB, indicating that DRCB had much better dispersion in aqueous media than CB. Cotton fabric was effectively dyed with DRCB, providing excellent color depth of 60 (K/S value) with dry rubbing and wet rubbing/washing color fastness of Grade 4 and Grade 3, respectively. DRCB dyed cotton fabric exhibited outstanding anti-UV and anti-static properties, with no significant difference in softness and tensile property before and after dyeing. This research proposed a new method to solve nanoparticle agglomeration and prepare textile dyes with excellent self-dispersivity and reactivity.

A novel PDA/POSS transition layer on the surface of UHMWPE fibers by co-depositing to improve the mechanical properties of composites

The surface treatment of ultra-high molecular weight polyethylene (UHMWPE) fibers is one of the key technologies for the application of UHMWPE fibers composites. In this paper, the interface transition layer of polydopamine (PDA) and polyhedral oligomeric silsesquioxane (POSS) co-deposited on the surface of corona pre-treatment fiber fabric is used to the uniform and efficient distribution of loads between the fibers and the resin matrix, especially to significantly improve the flexural modulus of UHMWPE fiber fabric composites. Under 2.5 kW corona pre-treatment, 4 g/L of dopamine hydrochloride and 2 wt% of γ-Aminopropyl triethoxysilane aqueous solution, the impact strength, flexural strength, and modulus of UH-C2.5@PDA/PA2 fiber fabric/epoxy composites are greatly improved to 218.6 kJ/m2, 151.7 MPa, and 7.8 GPa, respectively, which are 72 %, 106 % and 143 % higher than those of the untreated UHMWPE fiber composites. It may be attributed to: (1) the corona pre-treatment of UHMWPE fiber induces larger amount of active sites on fiber surface and higher surface energy, leading to a better wettability and adhesion with the matrix resin; (2) the mechanical interlocking engagement between the fibers and nano-POSS particles effectively prevents fibers extraction from the matrix resin and increases the friction of relative sliding; (3) POSS can strengthen the transition layer. The failure of UHMWPE fiber reinforced composites can be mainly attributed to energy absorption of matrix resin fracture, interface damage and relative sliding between matrix resin and fibers, fiber yield deformation and fiber fracture.

Development and mechanical properties of nano SiO2 modified photosensitive resin for high-strength and high-brittleness 3D printing in rock reconstruction

3D printing technology, as a rapid prototyping method, can accurately reconstruct the internal structural characteristics of samples, making it highly promising for rock engineering applications. However, current 3D printing materials used to reconstruct rocks suffer from low strength and high ductility, which is inconsistent with the high strength and brittleness of natural rocks. This paper explores the use of silane coupling agents KH550 (γ-aminopropyl triethoxysilane) and KH570 (γ-methacryloxypropyl trimethoxysilane) to modify nano SiO2 powder. Through sample preparation and uniaxial compression tests, the mechanical properties and failure characteristics of the modified nano SiO2 powder were analyzed. The results indicate that, using the preparation method with a mass ratio of E-44 epoxy resin, KH550 modified nano SiO2 powder, and 593 curing agent at 80:40:26, the samples achieved an uniaxial compressive strength of up to 30.55 MPa without enhanced brittle post-processing. The failure characteristics exhibited significant axial tensile damage. Additionally, combining CT scanning technology demonstrated that the structural and mechanical properties of the samples can be effectively reproduced. Therefore, the 3D printing materials discussed in this paper provide a viable reference for accurately reconstructing high-strength and high-brittleness rock masses.

Exploration of self-crosslinking induced surface modification using APTES on the PA RO membrane for excellent anti-fouling performance

The physicochemical properties of the polyamide reverse osmosis (PA RO) membrane surface play a crucial role in membrane fouling. In this work, a silicon-based material, γ-Aminopropyl triethoxysilane (APTES), was incorporated onto the PA membrane surface by self-crosslinking induced surface modification to improve its antifouling properties. FTIR and XPS analyses reveal that APTES primarily bonded to the pristine PA membrane via amidation between –NH2 groups in APTES and residual –COCl groups on the membrane surface, and then combined with each other to form Si–O–Si groups (even Si–O–Si networks). The incorporation of APTES reduces the membrane surface energy and roughness, and the surface potential of the membranes can be adjusted by varying the APTES addition. Meanwhile, the pure water permeance of the APTES-PA membrane reached ~3.77 LMH/bar while maintaining a NaCl rejection of ~98.65%. Additionally, although the negative charge of the APTES-PA (M0.15) membrane increases, the antifouling against electropositive small molecular foulants is enhanced, mainly due to the low-surface-energy of the APTES-modified layer. Furthermore, the stability of the APTES-modified layer in the presence of electronegative small molecular foulants with strong decontamination capabilities can be reinforced by a simple high-temperature heat treatment. Broadly speaking, surface modification of the PA RO membrane by APTES combining grafting with self-crosslinking induced method is beneficial for its anti-fouling and reuse.

PREPARATION PROCESS AND INTERFACE MODIFICATION ON THE MECHANICAL PROPERTIES OF BAMBOO FIBER/ POLYPROPYLENE CARBONATE COMPOSITES

In this study, bamboo fiber (BF) and polypropylene carbonate (PPC) were used to prepare BF/PPC composite materials. The single factor test combined with orthogonal experiment was used to investigate the effects of different hot pressing process conditions (hot pressing temperature, hot pressing pressure and hot pressing time) on the mechanical properties of BF/PPC composites. Based on the hot pressing process results, the filler nano-calcium carbonate (Nano-CaCO3), γ-aminopropyl triethoxysilane (KH550) and maleic anhydride (MAH) were added respectively to the composites to improve the interface between BF and PPC in order to increase the mechanical properties of the composites. The results showed that the reasonable preparation conditions of BF/PPC composites with the best mechanical properties were set at 170°C, under 1.9 MPa for 10 min. Compared with PPC samples, the tensile modulus, bending modulus and impact strength of BF/PPC composites could be increased to 102%, 38.69% and 65.13%, respectively. The optimal interface modification treatments have been proved that nano-CaCO3 with 10% content could increase the tensile modulus and impact strength to 70.53% and 65.84%, while the best result for the bending modulus of BF/PPC composites was modified with MAH with 2.5% content, which could increase to 28.46%.

Enhancing durability of superhydrophobic surfaces via nanoparticle-induced bipolar interface effects and micro-nano composite structures: A femtosecond laser and chemical modification approach

Superhydrophobic coatings are vital in energy, aerospace, and chemical engineering, while their complex preparation and limited durability hinder widespread application. Therefore, inspired by the unique structures of hydrophobic cotton surfaces and mosquito eyes in nature, a durable aluminum alloy superhydrophobic surface is developed using a combination of femtosecond laser and chemical modification methods. Initially, porous microneedle micro-nanostructures are ablated on the surface of the aluminum alloy via femtosecond laser technology. Then, epoxy resin modified with γ-aminopropyl triethoxysilane (KH550) forms a covalently bonded intermediate layer. Finally, biphasic silicon dioxide (BP-SiO2) nanoparticles modified by hexadecyltrimethoxysilane (HDTMS) are used to construct the top hydrophobic layer. The covalent interface interactions between the aluminum alloy substrate and the intermediate layer, as well as between the intermediate layer and the top layer, significantly enhance the durability of the superhydrophobic surface. The prepared F-M@KH-EP/BP-SiO2 coating exhibits outstanding superhydrophobic properties, with a water contact angle (CA) as high as 168.56° and a sliding angle (SA) as low as 1.52° More encouragingly, the composite coating maintains its excellent water resistance even when subjected to harsh mechanical durability damage, including sandpaper wear, tape stripping tests, water drop and sand impact tests. Moreover, the prepared coatings maintain distinguished non-wettability in harsh operating conditions such as corrosive liquid environments, ultraviolet radiation, ultrasonic vibration, etc. Additionally, the coating demonstrates remarkable self-cleaning properties. Superhydrophobic surface durability is significantly enhanced by combining nanoparticle-induced bipolar interface effect and micro-nano structures. These findings provide theoretical reference for the design and application of durable superhydrophobic coatings.

Preparation and characterization of biochar/polypropylene composites from recycled waste plastics and agricultural waste-reed straw

To alleviate the increasingly serious plastic pollution problem, developing biomass-plastic composite materials has become a research hotspot. In this study, waste polypropylene (PP) and reed biochar (RC) are used as raw materials to prepare biochar/polypropylene composites (BPCs), and γ-aminopropyl triethoxysilane (KH550) is used as an interfacial modifier to improve the interficical compatibility between RC and PP. Benefiting from the coupling effect of KH550, the obtained KH550-modified reed charcoal/polypropylene (K-RC/PP) composites exhibit enhanced tensile and bending strengths compared to the RC/PP. When 2.4 wt% of KH550 is applied, the tensile and flexural strengths of K-RC/PP reach 22.77 MPa and 49.6 MPa, respectively. Moreover, the interfacial modification simultaneously improves the thermal stability and hydrophobicity of the composites, which not only significantly reduces the fire risks but also improves the durability of the material. This work provides a feasible solution for developing biochar/plastic composites with excellent mechanical performances and high fire safety.

Fire-safe thermoplastic polyurethane created by a novel silane-containing phosphate

Phosphate is a kind of effective flame retardant for thermoplastic polyurethane (TPU), but it always results in great damage to mechanical properties. Herein, an organic silane-containing phosphonate (CTA-APTES) was prepared by 3-[Hydroxy (phenyl) phosphoryl]propanoic acid, tyramine and γ-aminopropyl triethoxysilane to simultaneously improve the fire safety and decreasing the mechanical loss of TPU. At the loading of 5.0wt%, TPU/CTA-APTES5 passed the UL-94 V-0 rating, and its limiting oxygen index was 28.5%, reaching the non-inflammable grade. While showing remarkable flame-retardant effect on TPU, just as important, the tensile strength and elongation at break of TPU/CTA-APTES5 were 11.34 MPa and 244.5% respectively, increased by 85% and 1471% compared with those of control sample TPU/CEPPA-TA5, remarkably reducing the damage of phosphate to mechanical properties of the substrate. This work provides an efficient strategy to utilize silane-containing phosphate to fabricate high-performance fire-safe TPU.

Improved dielectric and breakdown traits of polymer composites filled with KH-550 encapsulated multilayer black phosphorus

Polymer/particles composites are attractive for dielectric energy-storage, but they express difficultly-reconcilable conflict in high dielectric constant and breakdown strength. Here, multilayer black phosphorus (BP) coated by γ-aminopropyl triethoxysilane (KH-550) as filler, and poly(vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) (P(VDF-TrFE-CFE)) as matrix were used to prepare composite films. KH-550 encapsulation enhances BP/matrix interfacial compatibility. Dielectric constant of polymer/BP@KH-550 composite is ∼207 at 20 Hz when filler load is 10 wt% (dielectric loss ∼0.11), combined with direct-current breakdown strength of ∼288 MV m−1. This work is beneficial to facile preparation of dielectric composites with well-balanced dielectric and breakdown properties for capacitive energy-storage.

Superior mechanical performance polyurethane-silicone coatings for synergistic antimicrobial and antifouling coatings

With the increasing awareness of marine ecological environment, biocide-free marine antifouling coatings have been gaining increased attention in the field of marine antifouling. Among all the antifouling approaches, constructing fouling-release coatings (FRCs) may be the most effective and economical way caused by the biocide-free. However, the low mechanical strength, weak adhesion to substrates, and poor static fouling resistance of traditional silicone-based FRCs, which limiting their applications. In this work, we synthesized a polyurethane with hydroxyl terminated polydimethylsiloxane (PDMS), polytetrahydrofuran (PTMG) and isophorone diisocyanate (IPDI) as main chains, 2,2'-Bis (hydroxymethyl)butyric acid (DMBA) as chain extender, and γ-aminopropyl triethoxysilane (KH-550) as crosslinker by condensation polymerization. Meanwhile, Triclosan (TCS) was used as an antibacterial agent and mixed into the polymer system with uniformly dispersed. We introduced urethane groups into silicone, which improved the mechanical strength (ultimate tensile strength: 1.379 MPa, elongation at break: 282%). As a result, the laboratory bioassays using bacteria (E. coli, and S. aureus) showed that the anti-bacterial efficiency could respectively reach ∼95% and ∼93%, which demonstrated an outstanding antifouling property of the D:K = 0.7:1.3/1.0. This work overcomes the low strength issue of traditional fouling-release coatings and provides a simple strategy for silicone-based polyurethane antifouling coatings.

Starch microsphere silicon-boron crosslinker for low concentration hydroxypropyl guar gum based fracturing fluid

Hydroxypropyl guar gum (HPG) is a critical thickener to increase viscosity and lubrication to improve the water-based hydraulic fracturing efficiency. However, current crosslinkers require a large amount of HPG (>0.3 wt%) to form gel with sufficient viscosity, and high concentrations of HPG may cause adverse effects to the production and the environment. In this study, a novel starch microsphere silica‑boron crosslinker (SMSB) was developed using starch microspheres as a carrier and γ-aminopropyl triethoxy silane (KH550) as a modifier with an in-house method. Both the rheology and surface reactions of the SMSB-HPG crosslinking system were studied using multiple laboratory experiments and molecular dynamics simulation. The results showed that SMSB crosslinker caused multi-site cross-linking with low concentration (only 0.2 wt%) of HPG molecules, reducing the twisting of single molecular chain in the crosslinking system, enhancing the cross-linking strength between molecular chains, and making HPG molecular chains stretcher in the aqueous solution. The apparent viscosity and viscoelasticity of the HPG system were substantially higher than the organoboron crosslinker, and the temperature resistance of the SMSB-HPG crosslinking system was up to 140 °C. This study provides an alternative green crosslinker for more sustainable industrial applications and provides theoretical basis for the modification of biomaterials.

Fabrication and characterization of flexible natural cellulosic fiber composites through collaborative modification strategy of sodium hydroxide and γ-Aminopropyl triethoxysilane

The primary purpose of this work is to study the fabrication of a flexible natural cellulosic fiber composite. In this respect, natural cellulosic fiber was obtained by modified poplar wood fiber through sodium hydroxide (NaOH) and γ-Aminopropyl Triethoxysilan. Then, the composites were fabricated by hot-pressing the modified wood fibers and polyurethane following characterization. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and scanning electron microscope (SEM) observation results confirmed that some of the hemicellulose and lignin were removed from wood fibers after NaOH modification and successfully grafted with alkoxy structures after KH550 modification. NaOH&KH550 modification improved the interfacial compatibility between poplar wood fibers and polyurethane. The flexibility of the composites was improved (the slenderness value was reduced by 113 %), allowing flexible deformations such as bending, twisting, and knotting. In addition, thermal stability, tensile strength (increased by 105 %), elongation at the break (increased by 125 %), and water resistance were increased. This flexible natural cellulosic fiber composite is expected to be applied in the veneering of curved materials and special-shaped structure furniture, providing a theoretical basis for improving the added value of wood-based composites.

Synthesis, drug loading and release study of spherical bioactive glass regulated by two templates

In this paper, the particle size and morphology of spherical biogalsses(BGs) were regulated by changing the amount of catalyst and templating agent using the dual template method. The prepared BGs had good morphology, dispersibility, and rapid induction of hydroxyapatite generation. The cell activity was above 75 % after co-culture of BG extracts with mBMSCs cells. The surface modification of BG was carried out by γ-aminopropyl triethoxy silane (KH-550) to obtain amino functionalized BG (BG-NH2), which was then loaded doxorubicin hydrochloride (DOX) to obtain BG-DOX. The maximum loading of BG was 19.2 % and the encapsulation rate was 91.8 %. The drug release rate of BG-DOX was proportional to specific surface area, and it was capable to release DOX at high concentration for up to 10 days, which can be a good drug carrier.

Metallized liquid crystal polymer with low interfacial roughness and excellent adhesive strength based on semi-additive process for high-frequency signal transmission

Fifth-generation communication (5G) with the feature of high frequency puts forward harsh requirements on the roughness of the transmission lines due to the skin effect. Metallization liquid crystal polymer (LCP) with low interfacial roughness and high adhesive strength simultaneously poses a huge challenge for the modern electronics. Herein, based on semi-additive process, molecular grafting is reported to highly bridge smooth LCP substrate and thickened copper layer by chemical bonds. The process comprises the wettability of LCP surface tuned via oxygen plasma with negligible roughness changes. γ-aminopropyl triethoxysilane (APTES) plays a role in the integration of LCP substrate and metal layer. Followed by electroless plating, a thin nickel is planted on LCP as conductive seeds for electroplating copper. Compared with addition manufacturing, which directly coarsens the interface of circuits, semi-addition process just etches the edge of circuits. Through APTES grafting, 10 μm thick copper on LCP substrate reaches to the level of 5B according to the criteria of ASTM D3359, overcoming the trade-off between low interfacial roughness and high adhesive strength of existing techniques. Additionally, the interfacial strengthening mechanism of APTES grafting is carefully investigated. The proposed grafting-assisted semi-additive process is potentials for scalable fabrication of high-frequency electronics on various substrates.

Preparation of phase change functional two-dimensional materials and the tribological properties

The mechanical properties and toughness of phase change materials are often weakened by defects which affect the application of matrix in tribology, and considering the hybridization of nanomaterials is able to increase the upper limit of materials’ performance. In this study, the in-situ polymerization of isopropylacrylamide was used on the surface of graphene and MXene to prepare a phase change two-dimensional composite with reversible phase change under specific temperatures. The composites were dispersed in epoxy resin matrix by KH550 (γ-Aminopropyl triethoxysilane) to realize phase change modulation of tribological properties. The results showed that the tribological properties of the modified epoxy resin coating realized friction reduction and anti-wear functions, and exhibited different tribological properties at different temperatures. The friction coefficient and wear rate of the composite coatings can be reduced to 0.1 % and 82.2 %, respectively, which is mainly attributed to the two-dimensional structure and physical characteristics of graphene and MXene, as well as the mechanical enhancement of the phase change homopolymer and their synergistic effects.

The effect of modified carbon-doped boron nitride on the mechanical, thermal and γ-radiation stability of silicone rubber composites

The developing nuclear technology has increased the need for radiation-resistant and shielding materials. It is crucial to study the radiation resistance of polymers in order to prevent safety incidents brought on by the degradation of polymer performance in a nuclear environment. In this work, γ-aminopropyltriethoxy silane (KH550) was successfully grafted onto carbon-doped boron (BCN) to obtain modified BCN (BCN-KH550), then BCN-KH550 was added in silicone rubber and refined and vulcanized. The elongation at break of silicone rubber composite doped with 0.3 phr BCN-KH550 can retain (54 ± 2)% of the initial value. The addition of BCN and BCN-KH550 both increases the initial decomposition temperature of the irradiated SR. The radiation caused changes in crystallinity and glass transition temperature (Tg) were measured using differential scanning calorimetry. The difference Tg of BCN-KH550/SR0.3 before and after irradiation is 0.9 °C higher than that of SR. It is supposed that BCN protects the side group of SR during irradiation through differential thermogravimetric analysis curve and gas phase infrared spectra of the irradiation-induced gas products. BCN and BCN-KH550 can lower the hydrocarbon, CO2 and CO production by side chain breakdown in both air and nitrogen atmospheres. The presence of BCN and BCN-KH550 decrease the radiation crosslinking of SR. The outcomes demonstrate that BCN-KH550 can reduce the effects of γ-radiation crosslinking on SR by declining side chain decomposition.

A green tanning method based on POSS-COONa and zirconium: Achieving cleaner leather production

In this study, a two-step green and clean tanning technology based on the polyhedral oligomeric silsesquioxane sodium carboxylate (POSS-COONa) and zirconium was studied to relieve the environmental pressure and resource strain caused by chrome tanning. Firstly, amino sesquisiloxane was prepared from γ-aminopropyl triethoxy silane by hydrolysis and condensation method, and then was substituted with sodium chloroacetate to form POSS-COONa. The POSS-COONa had crystallinity and maintained cube structure by X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). Subsequently, POSS-COONa combined with zirconium sulfate was applied in tanning process of goat skin. Compared with untanning, chrome tanning, zirconium tanning crust leather, the shrinkage temperature and thickening rate of combination tanning crust leather were 90.5 °C and 118.3 %, respectively. The tensile strength, tear strength, elongation at break and softness of the combination tanning crust leather were 26.4 MPa, 96.3 N/mm, 105.5 % and 6.5 mm. The scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) showed that combination tanning crust leather collagen fibers were braided more loosely, and POSS-COONa and zirconium sulfate could be uniformly distributed in the collagen fibers. The isoelectric point of the combination tanning crust leather (∼6.7) was similar to that of chrome tanning crust leather (∼7.7). Based on the above results, POSS-COONa combined with zirconium sulfate tanning has a broad prospect in green clean production.

Triple Silicon, Phosphorous, and Nitrogen-Grafted Lignin-Based Flame Retardant and Its Vulcanization Promotion for Styrene Butadiene Rubber.

In this study, we present an innovative environmental silicon-, phosphorus-, and nitrogen-triple lignin-based flame retardant (Lig-K-DOPO). Lig-K-DOPO was successfully prepared by condensation of lignin with flame retardant intermediate DOPO-KH550 synthesized via Atherton-Todd reaction between 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and γ-aminopropyl triethoxysilane (KH550A). The presence of silicon, phosphate, and nitrogen groups was characterized by FTIR, XPS, and 31P NMR spectroscopy. Lig-K-DOPO exhibited advanced thermal stability compared with pristine lignin supported by TGA analysis. The curing characteristic measurement showed that addition of Lig-K-DOPO promoted the curing rate and crosslink density to styrene butadiene rubber (SBR). Moreover, the cone calorimetry results indicated Lig-K-DOPO conferred impressive flame retardancy and smoke suppression. The addition of 20 phr Lig-K-DOPO reduced SBR blends 19.1% peak heat release rate (PHRR), 13.2% total heat release (THR), 53.2% smoke production rate (SPR), and 45.7% peak smoke production rate (PSPR). This strategy provides insights into multifunctional additives and greatly extends the comprehensive utilization of industrial lignin.