Silicone-modified Epoxy Research Articles

Preparation and characterization of waterborne silicone modified epoxy resin

AbstractSilicone modified epoxy resin was synthesized with bisphenol‐A epoxy resin (E51) and dimethyldichlorosilane (DMDCS), and waterborne silicone modified epoxy resin (WSER) was prepared. The WSER emulsion exhibited good stability with particle size ranging from 0.5 to 2 μm. Compared with waterborne epoxy resin (WER) cured film, the water resistance of WSER cured film was enhanced by the excellent hydrophobicity of DMDCS. Furthermore, the WSER cured film with 6% DMDCS showed better mechanical properties, and Shore hardness and tensile strength of that were greatly increased. Moreover, the corrosion resistance and ultraviolet (UV) aging resistance of WSER cured film were obviously improved compared to WER cured film.Highlights Dimethyldichlorosilane (DMDCS) was employed to modify bisphenol‐A epoxy resin (E51). Waterborne silicone modified epoxy resin (WSER) was prepared by phase inversion method. WSER cured films did better than WER cured film in water resistance and mechanical properties. WSER cured films showed good corrosion resistance and ultraviolet aging resistance.

Experimental Study on Improving the Impermeability of Concrete under High-Pressure Water Environments Using a Polymer Coating

The concrete lining of high-pressure water conveyance tunnels permeates under high-pressure water. Dense and hydrophobic coating can effectively improve the impermeability of concrete. However, the coating exhibits varying impermeability in different high-pressure environments, which can even lead to coating detachment or damage. The objectives of this study are to improve the high-pressure impermeability of concrete by using a polymer coating, and to study the varying impermeability through experiments. This study applied a polymer coating called SCU-SD-SP-II (SSS) to concrete surfaces, and it formed a composite protective layer with an epoxy-modified silicone (EMS) coating. A series of high-pressure impermeability tests were conducted to study the seepage regulation of the coated concrete and the failure mechanism of the SSS coating under cracks in the concrete. The results indicate that the SSS coating has excellent impermeability. Pressurized water of 3 MPa could not permeate the SSS coating with a thickness of 0.5 mm within 24 h. Under both external and internal water pressure conditions, the SSS coatings improved concrete impermeability. Additionally, the average seepage height and relative permeability coefficient of the latter decreased by 49.6% and 71.2%, respectively, compared with the former. After concrete cracking, the SSS coating could withstand 3 MPa pressure on crack surfaces smaller than 1 mm. When the crack width was greater than 2 mm, the SSS coating deformed under 1 MPa pressure. As the pressure increased to 2 MPa or even 3 MPa, the SSS coating was punctured or torn due to stress concentration. This study provides new insights into the impermeability of concrete under high water pressure.

In situ construction of silicon-containing carbon layer by hyper silicone-branched structure endows epoxy/carbon fiber composites with high strength and ablation resistance

Epoxy/carbon fiber composites are widely used as structural materials in the aerospace field. Improving the ablation resistance of epoxy/carbon fiber composites is of great importance for the fabrication of highly integrated structural-thermal protection materials. In this study, a silicon-modified epoxy/carbon fiber composite was prepared by a hyperbranched structural design approach. By taking advantage of the excellent antioxidant properties of the silicone compounds generated by the pyrolysis of hyperbranched silicone structures, a dense char layer is rapidly constructed on the surface of composites. The characterization and thermal pyrolysis behavior of hyperbranched silicone-modified epoxy resins are analyzed. In the simulated aerodynamic environment of a high-speed vehicle (where the heat flow is 160 kW/m2), compared with epoxy/CF composites, the value of the mass loss rate of modified composites underwent a reduction exceeding 80%, accompanied by a 60.3 °C decrease in the maximum back-surface temperature. More significantly, the post-ablation mechanical properties were evaluated through a three-point bending test, revealing that the modified composites retained over 95% of their initial flexural strength and modulus after simulated pneumatic heating. This approach offers a new approach to manufacture structurally simple, integrated structure-thermal protection systems.

Applicability Evaluation of Modified Epoxy Resin in the Repair and Reinforcement of Ancient Building Timber Members

To investigate the potential of modified epoxy resin for repairing and strengthening historical wooden structures, this study utilized polyurethane and silicone-modified epoxy resin as the base, alongside a polyamine curing agent. The resin mixture was cured at ambient temperature, resulting in the creation of ten unique epoxy resin systems. Investigation into the chemical structure and alterations to the glass transition temperature were conducted. The study conducted tests and characterization of viscosity, curing rate, mechanical properties, stress failure mode, hygrothermal aging resistance, and bonding properties. The results reveal that the curing degree of the two modified epoxy resins is high after being cured at room temperature, and the chemical structure and curing rate show insignificant changes. The range of the glass transition temperature for the modified epoxy resin is between 61.31 °C and 70.51 °C. The incorporation of polyurethane and silicone molecular chains into the epoxy resin cross-linking curing system enhances the toughness of the epoxy resin. The modified resin achieves a maximum elongation at break that is 5.18 times greater than that of the unmodified resin, along with a maximum tensile strength and a compressive strength that are 7.94 and 1.74 times, respectively, higher than those in the Chinese technical specifications for the maintenance and reinforcement of ancient wooden structures. The increase in toughness changes the failure mode of the cured epoxy resin. The modified epoxy resin exhibits great bonding ability to aged wood, with a shear strength of up to 9.6 MPa along the grain. As a result, the modified epoxy resin meets the requirements for the reinforcement and repair of the timber members of ancient buildings.

Enhanced microwave absorption and corrosion resistance of carbonyl iron encapsulated by silicone modified epoxy resin

The novel silicone modified epoxy resin (ER) was synthesized and used to encapsulate the carbonyl iron powders (CIP) with core–shell structure by in-situ polymerization method. The silicone modified epoxy resin coating was introduced to enhance both microwave absorption and corrosion resistance of carbonyl iron. Microstructure analysis demonstrated that CIP were densely covered with ER shell. Hydroxyl (–OH) and amino group (–NH2) present in silicone-modified epoxy resin, and chemically interact with the metal oxide layer on carbonyl iron to form covalent bonds or hydrogen bonds, improving interfacial adhesion and uniform dispersion of CIP. The ER shell effectively strengthens the microwave absorption ability and corrosion resistance of CIP. The reflection loss peak reached − 52.1 dB and effective absorption bandwidth achieved 7.8 GHz (10.2 GHz − 18 GHz). The epoxy resin coating significantly reduced the charge transfer resistance (Rct) and corrosion current density (Jcorr), indicating improved corrosion protection. Polarization resistance (Rp) and corrosion rate (CR) analysis further verified corrosion resistance. The epoxy resin-coated CIP exhibit excellent microwave absorption and corrosion resistance, indicating widespread application in anti-electromagnetic interference field.

Preparation and Properties of Environmentally Friendly, Hydrophobic, Corrosion-Resistant, Multifunctional Composite Coatings

With the continuous exploitation of the marine resources, the equipment should meet the marine complex working environment. In this study, a type of environmentally friendly coating was prepared. Based on low surface energy environmental protection and anti-fouling, a film forming material with water-based epoxy-modified silicone resin emulsion was prepared. And industrial fillers were added to give it both inorganic and organic properties. Meanwhile, various contents of graphene oxide (GO) were added in the coating system. The coating properties were comprehensively analyzed, and the optimal GO content was obtained as 0.1 wt. %. The composite coating was studied by seawater immersion experiments, and the failure process of the coating in was proposed. The composite coating prepared in the present study has both environmental protection and hydrophobic anti-fouling characteristics, and its comprehensive performance is excellent through various performance evaluations, i.e., it meets the requirements of long-term coating, environmental friendliness and anti-fouling and corrosion resistance.

Lignin-based silicone-modified epoxy resin with enhanced strength and toughness

Epoxy composites with enhanced strength and toughness are vital in the field of electronic packaging material. This study proposes the synthesis of a novel lignin-based silicone-modified epoxy resin (LSE) to improve the strength and toughness of epoxy resins (EPs) simultaneously. The results demonstrate that the glass transition temperature, β-relaxation temperature, and crosslinking density of the composites decreased with increasing LSE content. Compared to neat EP, the toughness properties, including the impact strength and critical stress intensity factor (K1C), of the 3 wt% LSE/EP composite improved by 16.25 % and 25.28 %, respectively. Meanwhile, the mechanical properties such as the tensile strength, bending modulus, and bending strength enhanced by 25.81 %, 16.21 %, and 42.43 %, respectively. Therefore, the LSE simultaneously exhibits toughening and strengthening effects. Based on the fracture surface evaluation results obtained using a scanning electron microscope and a nano-FTIR, these effects are attributed to the formation of interpenetrated networks and improved interfacial effects by the LSE. As an efficient fortifier and flexibilizer, LSE shows great promise for the preparation of EP packaging materials.

Preparation and Properties of Phenolic Epoxy Modified Silicone Resin

Phenolic epoxy resin (F51) was first reacted with silane coupling agent (3-aminopropyl)triethoxysilane (KH550) to form a silanized phenolic epoxy resin (SPER); then the SPER was copolymerized with methylphenyl silicone resin (MPS) to synthesize phenolic epoxy modified silicone copolymer (PEMSC). The chemical structure of the PEMSC was characterized by FT-IR. The results of tensile strength and shear strength measurements indicated that the successful introduction of F51 significantly improved the mechanical and adhesive properties of the PEMSC; compared with the PEMSC with 10 phr of F51 added, the tensile strength and shear strength of the PEMSC with 40 phr increased by 8.5 and 3.5 times respectively. The TGA and DTGA analysis showed that the initial thermal decomposition temperature and the residual weight of PEMSC at 800 °C decreased compared to MPS, but the temperature corresponding to the maximum thermal decomposition rate in the second stage increased. Qualitative analysis was conducted on the decomposition products of PEMSC using gas chromatography coupled with mass spectrometry (GC-MS). The results showed that the relative content of aromatic hydrocarbons and their derivatives in the decomposition products of PEMSC was 64.11%, and the relative content of cyclic trimers and higher cyclomers was 20.41%.

Synthesis of epoxy resin/silicone rubber interpenetrating polymer network for ablation thermal protection coating

Silicone modified epoxy resin (EPS) is synthesized through the condensation reaction of methoxy and hydroxy groups, which improves the compatibility of epoxy resin and silicone rubber (SR). EPS and SR are blended and cured at room temperature. Through the self-locking method of chain segments, an EPS/SR interpenetrating polymer network (IPN) with limited microscopic morphology and excellent macroscopic properties is obtained, which effectively solves the problems of Pure SR's low binding force and poor thermal properties. Furthermore, an IPN-based ablation thermal protection coating (ATPC) is also prepared. Compared with the classic SR-based ATPC, the IPN-based ATPC has higher mechanical strength and better ablated surface state, and a stable carbon layer is formed during the ablation process, which is carried out through a coordinated mechanism of thermal blockage and thermal barrier.

Research on Properties of Silicone-Modified Epoxy Resin and 3D Printing Materials.

A kind of organosilicon intermediate was prepared using isophorone diisocyanate (IPDI), hydroxyl silicone oil (HSO), and hydroxyethyl acrylate (HEA). The organosilicon modification of epoxy resin was realized by introducing a -Si-O- group into the side chain of epoxy resin by chemical grafting. The effects of organosilicon modification of epoxy resin on the mechanical properties systematically discuss its heat resistance and micromorphology. The results indicate that the curing shrinkage of the resin was decreased and the printing accuracy was improved. At the same time, the mechanical properties of the material are enhanced; the IS and elongation at break (EAB) are enhanced by 32.8 and 8.65%, respectively. The brittle fracture is changed to a ductile fracture, and the tensile strength (TS) of the material is decreased. The glass transition temperature (GTT) of the modified epoxy resin increased by 8.46 °C, and T50% and Tmax increased by 1.9 and 6 °C, respectively, indicating that the heat resistance of the modified epoxy resin was improved.

An Aluminum-Based Microfluidic Chip for Polymerase Chain Reaction Diagnosis.

Real-time polymerase chain reaction (real-time PCR) tests were successfully conducted in an aluminum-based microfluidic chip developed in this work. The reaction chamber was coated with silicone-modified epoxy resin to isolate the reaction system from metal surfaces, preventing the metal ions from interfering with the reaction process. The patterned aluminum substrate was bonded with a hydroxylated glass mask using silicone sealant at room temperature. The effect of thermal expansion was counteracted by the elasticity of cured silicone. With the heating process closely monitored, real-time PCR testing in reaction chambers proceeded smoothly, and the results show similar quantification cycle values to those of traditional test sets. Scanning electron microscope (SEM) and atomic force microscopy (AFM) images showed that the surface of the reaction chamber was smoothly coated, illustrating the promising coating and isolating properties. Energy-dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and inductively coupled plasma-optical emission spectrometer (ICP-OES) showed that no metal ions escaped from the metal to the chip surface. Fourier-transform infrared spectroscopy (FTIR) was used to check the surface chemical state before and after tests, and the unchanged infrared absorption peaks indicated the unreacted, antifouling surface. The limit of detection (LOD) of at least two copies can be obtained in this chip.

Organic silicone-modified waterborne epoxy coatings using aqueous curing agents technology

PurposeThe silicone modifications of two-component epoxy resin coatings are commonly built on epoxy resins rather than on epoxy curing agents. The silicone-modified epoxy curing agent system is rarely reported yet. This study aims to prepare the polysiloxane (PS)-modified waterborne epoxy coatings based on aqueous curing agents technology.Design/methodology/approachWaterborne epoxy curing agents with different contents of terminal epoxy PS were synthesized by reacting with triethylenetetramine, followed by incorporating of epoxy resin (NPEL-128) and polyethylene glycol diglycidyl ether. The waterborne epoxy coatings were prepared with the above curing agents, and their performance was investigated through thermogravimetric analysis, scanning electron microscopy, mechanical characterization, gloss measurement, chemical resistance test and ultraviolet (UV) aging experiment.FindingsThe results showed that the epoxy coating prepared by silicon-modified curing agent has higher gloss, better chemical resistance and UV resistance than the coating from unmodified curing agent with terminal epoxy PS and commercially available waterborne epoxy curing agent (Aradur 3986), as well as the competitive mechanical properties and heat resistance. Reduced water absorption on fibrous paper was also obtained with the help of silicon-modified curing agent.Originality/valueThese findings will be valuable for resin researchers in addressing the modification issues about waterborne epoxy resin and curing agent.

Protective effect of silicone-modified epoxy resin coating on iron-based materials against sulfate-reducing bacteria-induced corrosion

The annual economic loss caused by microbiologically influenced corrosion (MIC) is over 140 billion US dollars worldwide. A sizable proportion (30 %) of MIC is caused by sulfate-reducing bacteria (SRB). Herein, a silicone-modified epoxy resin coating was designed with the aim of reducing the rate of SRB-induced corrosion. The epoxy resin (E-51) was modified with heptamethyltrisiloxane and 3-aminopropyltriethoxysilane (APTES). Compared to the pure epoxy coating (E-51), the modified coating (TAK550/E-51) had a better protective effect against acid- and SRB-induced corrosion owing to its macroscopic and microscopic morphology. Electrochemical impedance spectroscopy revealed that the impedance of TAK550/E-51 coating was 1.5-times higher than that of the E-51 coating, providing it with higher corrosion resistance. In addition, the TAK550/E-51 coating had a lower corrosion current density (icorr = 3.30 × 10−9 A·cm−2) and higher corrosion potential (Ecorr = −0.04 V) than the E-51 coating. The thermal stability of the TAK550/E-51 coating was improved compared to that of the pure epoxy resin coating, with a 9.2 °C higher initial decomposition temperature (T5%), 40.8 °C higher 50 % weight-loss temperature (T50%), and doubled carbon residue rate. The elemental composition and valence state of the coating surface were examined by X-ray photoelectron spectroscopy after immersion in SRB-containing solution for different time periods, which revealed the antibacterial and anticorrosion mechanisms of the TAK550/E-51 coating. The results reported in this paper demonstrate that the silicone-modified epoxy coating has good MIC resistance and can be used as a protective coating for iron-based materials that are susceptible to MIC in industries such as marine engineering and oil exploration.

Epoxy-modified silicone resin based N/P/Si synergistic flame-retardant coating for wood surface

Flammable wood has a negative impact on safety, however flame-retardant coatings can help to mitigate these risks. In this work, the epoxy-modified silicon (SiR) coating was formed by the condensation of dimethyldiethoxysiloxane with 3-glycidoxypropyltrimethoxysilane (KH-560), while the resin cured by nitrogen-containing phosphorus flame-retardant (PTDP) curing agent. The flame-retardant coating (PTDP/SiR) has outstanding hardness, water resistance, solvent resistance and it is appropriate for utilizing in wood surfaces. Meanwhile, PTDP/SiR-1 exhibits obvious flame retardancy. The PTDP/SiR-1-coated spline received a UL-94 V-1 rating and a 31.0% LOI, compared to 26.0% and 21.5% for the control coating and uncoated splines, respectively. Compared with the control spline, the peak heat release rate (pHRR) decreased by 23%. SEM, XPS and TGA-FTIR revealed the N/P/Si synergistic flame-retardant mechanism. The mechanism of improving the flame retardancy is due to a dense char layer, incombustible gas, and phosphorus-containing segment formed by pyrolysis. The combination of these factors improves the coatings flame retardant.

Synthesis of DC–3074 and Z–1 Silicones Modified Epoxy Resin and Comparison of Salt Spray Resistance

In order to improve the chemical resistance of epoxy resin and its toughness and corrosion resistance, in this paper, silicone modified epoxy resin was prepared with epoxy resin and two kinds of silicones, Dow Corning DC–3074 and Chenguang Z–1, as raw materials and dibutyltin dilaurate (DBTDL) as catalyst. The structure of the modified epoxy resin was characterized by Fourier transform infrared (FTIR) spectrometer and its performance was tested. The results showed that the epoxy resin modified by DC–3074 had better salt spray resistance compared with the Z–1. Therefore, the DC–3074 was selected as the epoxy resin E–51 modifier. The silicone modified resin was further synthesized with E–51 as the matrix resin, 12.5% DC–3074 silicone as the modifier, and 0.5% DBTDL as the catalyst. The obtained cured coatings showed good performance with the following results: product fineness of 20–25 μm, solid content of more than 95%, surface drying time of 25 min, smooth appearance, hardness of 2 H, adhesion level of 0, and salt spray resistance time of 432 h. The prepared modified epoxy resin coating has good salt spray resistance and good application prospect.

Improvement in Thermal Conductivity of Through-Plane Aligned Graphite Flake/Silicone Modified Epoxy Resin Composites

We describe, here, our study of the thermal conductivity (TC) properties of silicone modified epoxy resin (SEP) films which were prepared by blending low molecular weight SH-023-7 silicone resin with Dow 332 epoxy resin as the matrix of composites using graphite flakes (GF) as a thermally conductive filler. The SEP/GF composites with different filler contents and SEP/vertically aligned GF (AGF) composites utilizing various magnetic field intensities were fabricated, and the TC, and thermal stability (TS) were characterized by thermal gravimetric analysis, and the morphology was observed by scanning electron microscopy (SEM). According to the experimental results, both the TC and TS increased with the increasing addition of filler. When the weight fraction of M (M = ) was 60 wt%, the TC of the composites was 1.38 W/mk, which was 5.52 times higher than that of pure SEP (0.25 W/mK). In addition, the addition of graphite also increased the decomposition temperature of the composites. The vertically aligned GFs resulted in effective, vertical, thermally conductive pathways in the SEP matrix, and the SEP/AGF composites exhibited much higher through-plane TC compared to the non-orientated SEP/GF composites. The SEP/AGF reached 5.66 W/mK, which was approximately 4.1 and approximately 23 times higher than 60 wt% SEP/GF and pure SEP, when the nano-Fe3O4 content was 0.4 g, the strength of magnetic field was 0.65 T and the added amount of M was 60 wt%. In addition, by SEM observation, when the flake graphite was found in the direction of the magnetic field orientation, the graphite formed heat conduction channels touching each other in the magnetic field direction, improving the TC. Using XRD analyses the orientation degree of the graphite in the composite showed that the graphite obviously changed its internal orientation in the composite material when subjected to the magnetic field in the SEP melt.

The Interfacial Structure and Adhesion Mechanism of N-(2-Aminoethyl)-3-aminopropyltrimethoxysilane and Epoxy Modified Silicone Tie-Coating to Epoxy Primer.

The matching application of silicone antifouling coating and epoxy primer is a major problem in engineering. Novel epoxy-modified silicone tie-coating was prepared to tie epoxy primer and silicone antifouling coating. Firstly, N-(2-Aminoethyl)-3-aminopropyltrimethoxysilane was mechanically mixed with bisphenol A epoxy resin to form silylated epoxy resin, then the silylated epoxy resin was uniformly mixed with hydroxy-terminated polydimethylsiloxane and a curing agent and catalyst for coating. An infrared spectrometer, differential scanning calorimeter and tensile tests were used to investigate the chemical structure, phase transition temperature and mechanical properties of the tie-coatings. The interlaminar adhesion of the matching coating system was tested and analyzed by a peel-off test and a shear test. Fracture morphology was observed by scanning using an electron microscope. The results showed that crosslinking density of the tie-coating, the elastic modulus and the tensile strength of the coating increased with an increasing epoxy content, but fracture elongation decreased. The shear strength of the matching coating system is 0.37 MPa, and it shows a good tie performance. The maximum anti-peeling rate of the tie-coating on the epoxy primer reaches 100%.

Hygrothermal Aging Characteristics of Silicone-Modified Aging-Resistant Epoxy Resin Insulating Material.

To study the improvement effect of silicone materials on the hygrothermal resistance of epoxy resin and the aging mechanism of silicone-modified insulation materials under hygrothermal conditions, diphenylsilanediol was added to epoxy resin as a modifier in various quantities to synthesize silicone-modified epoxy resin, and a hygrothermal aging test was carried out. Water sorption, surface contact angles and dielectric properties of the insulation material were measured, and scanning electron microscope (SEM), Fourier-transform infrared spectrometry (FT-IR) and frequency domain spectroscopy (FDS) were used to analyze the results. The results showed that under 10 wt%, the silicone-modified insulation materials exhibited lower absorption rate and better dielectric properties, including lower dissipation factors and lower dielectric constant during the hygrothermal aging process, while epoxy resin modified with excessive silicone material tend to show worse dielectric performance. Closer analysis found that diphenylsilanediol decreases the size of the cracks within the material during hygrothermal aging, indicating that cracks generated during the hygrothermal aging process may be the reason for the worse dielectric performance, and diphenylsilanediol improves the hygrothermal aging resistance mainly by slowing down the generation and growth rate of cracks. FT-IR results confirmed the existence of hydrolysis and found that the rate of hydrolysis does not change with the content of diphenylsilanediol. FDS results also indicated that modified materials contain less dipoles after hygrothermal aging.

Synthesis of a hydroxylamino-modified silicone oil for use in a polyacrylonitrile oil emulsion in carbon fiber production

In order to prepare a stable oil emulsion suitable for polyacrylonitrile (PAN) in carbon fiber production, a hydroxylamino-modified silicone oil (HA-PDMS) was synthesized by a three-step procedure and mixed with a commercial epoxy-modified silicone oil in water to prepare an oil emulsion of PAN (P-OE) in carbon fiber preparation. The structure of the intermediate products and P-OE were analyzed by FT-IR and 1H-NMR. The major properties of P-OE were investigated by a laser particle size analyzer, thermogravimetric analyzer and surface tension instrument and compared with those of the commercial one used in Japan (J-OE). The polyacrylonitrile solution in dimethyl acetamide was drawn by wet spinning and impregnated in P-OE and J-OE to obtain P-PAN and J-PAN, respectively, which were carbonized to obtain carbon fibers P-CF and J-CF. The Roder friction coefficient, hairiness and tensile strength of P-PAN, J-PAN, P-CF and J-CF were tested to compare the performance of the two kinds of oil emulsions for use in PAN-based carbon fiber production. Results show that the tensile strength of P-PAN is higher than that of J-PAN. Compared with J-CF, the tensile strength and tensile modulus of P-CF are higher and the hairiness is greatly reduced. P-OE is superior to J-OE for the use as an oil emulsion of PAN in production of PAN-based carbon fibers.

Synthesis of Epoxy-Modified Methyl Phenyl Silicone Resins for LED Encapsulation

The epoxy-modified silicones have the advantages of both epoxy and organic silicon. In this paper, a series of epoxy-modified methyl phenyl silicone resins were synthesized through the hydrosilylation reaction between 1, 2-epoxy-4-vinylcyclohexane and methyl phenyl silicone resins. The effects of catalyst dosage, reaction time and temperature on the products were further discussed to determine optimal reaction conditions. Then, the as-prepared epoxy-modified silicone resins were cured with methylhexahydrophthalic anhydride. The curing kinetics was investigated through differential scanning calorimetry (DSC). The curing conditions were determined as follows: 1-h curing at 80 °C for and subsequent 1-h curing at 110 °C. The as-prepared products exhibited high light transmittance (~ 90% at 450 nm), strong bonding, suitable hardness and sound waterproof performance. In addition, the introduction of methylphenylsiloxane chain significantly improved the heat resistance and UV resistance of cured products. The epoxy-modified silicone resins are ideal LED packaging materials.