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Silicone Resins & Oligomers

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Silicone Resins & Oligomers Silicone Resins & Oligomers R RAdding Si O Functionality, improving Durability and Reliability R Silicone Resins & Silicone Oligomers R O Si O O O O Si O O R O Si O R CONTENTS What are Silicone Resins and Silicone Oligomers? P3 Silicone Resins P4-12 Silicone Oligomers P13-19 ■ Structures of Silicone Resins P4 ■ Systems and Structures of Silicone Oligomers P13 ■ Types of Silicone Resins P4 ■ Features of Silicone Oligomers P13 ■ Features of Silicone Resins P4 ■ Types of Silicone Oligomers P13 ■ Cure Systems of Silicone Resins P5 Type A ■ Relationship between Compositions and ■ Product List P14 Characteristics of Silicone Resins P5 ■ Applications P14-15 ■ Product List P6 ● Organic Resin Modifiers ● Room Temperature Moisture Cure Coatings ■ Product Lineup P7 Type AR ■ Map of Structures and Features P7 ■ Product List P16 ■ Applications P8-10 ■ Applications P16 ● Heat Resistant Paints P8 ● Coupling Agents ● Weather Resistant Paints P9 Type R ● Resin Modifiers P9 ■ Product List P17 ● Electrical Insulation Coatings P10 ■ Main Products P18-19 ● Heat Resistant & Electrical Insulation Binders P10 Product Features & Packaging Options P20-21 ■ Main Products P11-12 Catalysts P22 Handling Precautions P23 2 Structures of Silicone Resins Solidify is possible What are Silicone Resins? Siloxane Structure: 3D Network structure On a molecular level, silicone resins are primarily made up of Molecular Weight: Medium to High siloxane units (Si-O-Si) which have a high bond energy. Functional Groups: <Reactive> Silanol Groups (Si-OH), Silicone resin coatings have many useful properties including heat resistance, Vinyl Groups (Si-CH=CH2), Hydrosilyl Groups (Si-H) excellent weatherability, superior dielectric properties and water repellency. <Non-reactive> Methyl Groups, Phenyl Groups Used as Resin alone Used as Organic Resin Modifiers ● Dehydration Condensation Cure Type: 1 Part Cure is available ■ Reaction mechanism ■ H Reaction condition: Heating Reaction Mechanism O O After Curing H O O O Si Si Before Curing O Organic resin Si H O H H O R R Dehydration Heating H O H O R O H H R Si R O O over 150°C O Condensation O Si Si Si O H Si O R O O Organic resin R R O O O Si Si O H R R Dehydration R O O R R O R Si O Si Si O O Condensation O R Si H H O O Si OR Si O Si Si H Si R Reaction O R O ■ O R O O Main Property & Application O R O Si O O Si Si R Si R R O O Si O H O H Heat resistance O H O H R H O H Weatherability Flame retardance ● Addition Cure Type: Low Cure Shrinkage ■ Reaction Mechanism H C H C H Before Curing After Curing Heating over 120°C R + R Si H Adding Platinum Catalyst H C O C O H H H Si C R C H Addition C H H Si H R H Reaction Si H C Heat resistant paints H H C C H H Si H H C C C H H R Methyl groups or Phenyl groups ■ Main Property & Application Heat resistance Industrial paints Electrical Insulation Weatherability Heat resistant paints Moisture proofing and Binders Polycarbonate flame retardants insulation for circuit board Structures of Silicone Oligomers Solventless (Silicone content 100%) What are Silicone Oligomers? Siloxane Structure: 3D Network structure Silicone oligomers are relatively low-molecular-weight silicone resins. Molecular Weight: Low These unique products can be used as resins on their own, Functional Groups: <Reactive> Alkoxy Groups (Si-OR), Acrylic Groups, Methacrylic Groups, they can be used to improve the properties of organic Epoxy Groups, Mercapto Groups and Vinyl Groups etc.. resins, or as modifiers to improve interfacial compatibility. <Non-reactive> Methyl Groups, Phenyl Groups Used as resins on their own Used as Organic Resin Modifiers ● Dealcoholization-condensation Cure Type: Curable at room temperature ■ Reaction Mechanism Reaction condition: Room temperature or heating (catalyst should be used together) ■ Reaction Mechanism Adding After Curing O R O Catalyst H H 1 Dealcoholization-condensation Before Curing O X R R + O O Si X Moisture Si O O X Organic resin Organic resin Si R X O O X X Si O in the air X O Si X X Si O O O Si O Dealcoholization- Si X O Si O Si O 2 Dehydration Condensation Si condensation O O O O X O Si O Reaction Si R O Organic resin Organic resin O R X R H O H X R O 3 Chemical Reaction of Acrylic or Epoxy Groups R O Alkoxy Groups X Methyl groups or Methyl / Phenyl groups and other organic functional groups ■ Main Property & Application ■ Main Property & Application Water repellency Weatherability High hardness Adhesion Weatherability Water resistance Body coatings Floor coatings Water repellent agents Substrate & Encapsulants Adhesives Paints for construction materials 3 Silicone Resins Structures of Silicone Resins All silicone products are composed of the four units shown below. Silicone resins are composed mainly of T units, and cure to form hard coatings with a 3D network molecular structure. Resins having D units (Di-functional) form flexible films, while those with Q units (Quadri-functional) will form films with higher hardness. Main Component M Units D Units T Units Q Units Mono-functional Di-functional Tri-functional Tetra-functional R3SiO1/2 R2SiO2/2 RSiO3/2 SiO4/2 R R R O R Si O O Si O O Si O O Si O R R O O R Reactive groups Model of Curing Silicone Resins ■ Before curing H ■ After curing O O O O O H H H O O Si Si H H O H Si O R R R O R Si O O R O H H Si Si O O R O O R O H Si Si O Heating Si O O O R R O R O O R Si O Si Si H R R Dehydration condensation O O R Si Si O O O Si reaction R O O Si Si O R R O O H Si R O Si H H O Si O Si O R R H O O R R O H Si O O H R Si Si H O R O O O Forming hard film with 3D network structure O H H R Methyl groups or Phenyl groups Features of Silicone Resins With their molecular backbone of siloxane units, silicone resins outperform organic resins in heat resistance, weatherability and dielectric properties. Some of their special features are described below. ■ Comparison of Silicone Resins and Organic Resins Features Silicone Resins [Structure: Si-O-Si ] Organic Resins [Structure: C-C , C-O-C ] Heat resistance Excellent ≤ 250°C Excellent ≤ 200°C Electrical properties Excellent Consistent across a wide range of temperatures Poor Decline in hot, humid conditions Low hygroscopicity High hygroscopicity Water resistance Excellent Poor (Due to the orientation of their Si-CH3) (Absorbed water does not dissipate easily) Weatherability Excellent Excellent ultraviolet resistance Poor Flame retardancy Excellent Poor Must be used with a fire retardant Adhesiveness Excellent Particularly to inorganic materials Excellent Particularly to organic materials Mechanical strength Poor Intermolecular force: Small Excellent Intermolecular force: Strong / Crystallinity: Strong Chemical resistance Poor Vulnerable to strong acids and bases Excellent 4 Silicone Resins Cure Systems of Silicone Resins Silicone resins generally rely on one of two cure systems: dehydration-condensation and hydrosilylation. The majority cure by dehydration-condensation. The cure conditions and advantages of each cure systems are described below. Cure Systems Cure Conditions Features ■ Structure Containing silanol groups Condensation Dehydration ■ One Componet ■ Catalysts Not necessary (But can be used to accelerate the reaction) reaction condensation Cure ■ Heating Necessary (Methyl type: 100°C to 200°C, Phenyl type: 180°C to 250°C) ■ Structure Containing –Si–CH=CH2 and H–Si– ■ Rapid Cure Addition Hydrosilylation ■ Catalysts Necessary (Platinum based catalysts) ■ Low Cure reaction ■ Heating Necessary (100°C to 150°C) Shrinkage Relationship With silicone resins, the cure speed, film hardness, heat resistance and other properties between Compositions and can vary greatly depending on the resin’s molecular weight, the types of organic Characteristics of Silicone Resins substituents and functional groups it contains. The charts below show the relationship between a silicone resin’s characteristics and its compositions, specifically the phenyl group content and ratio of T units to D units. Effects of Phenyl Group Content Rapid Cure Speed Slow Hard Soft Hardness Hard Low Flexibility High Excellent Heat Resistance 0 10 20 30 40 50 60 70 80 100 Ph/R (mol%) Effects of T Unit Content Slow Cure Speed Rapid Soft Hardness Hard High Flexibility Low Excellent Heat Resistance 0 10 20 30 40 50 60 70 80 100 T Units/ (T Units + D Units) (mol%) 5 Product List Non-volatile Compatibility Cure Product name Type content Solvent Hardness with organic Main applications Features speed 105°C×3 h % resins White flake, excellent heat resistance Heat resistant and KR-220L 100✽1 None Rapid High Low and flame retardance, flame retardant binders very little smoking by heatig Heat resistant and KR-220LP 100✽1 None Rapid High Low Powder type of KR-220L Methyl Type flame retardant binders Toluene, Heat resistant and Excellent heat resistance and KR-242A 50 Rapid High Low isopropyl alcohol flame retardant binders flame retardance Moisture proofing and KR-251 20 Toluene Rapid Medium Low Thin hard coating insulating coatings Moisture proofing and KR-112 70 Toluene, xylene Slow Low Medium Solvent resistant flexible coating insulating coatings KR-211 70 Xylene — — — Resin modification Excellent compatibility Excellent compatibility, KR-212 70 Xylene — — — Resin modification more flexible than KR-211 Moisture proofing and KR-255 50 Toluene, xylene Medium Medium Medium Glossy hard coating insulating coatings Excellent heat resistance and KR-271 50 Xylene Slow Low Medium Heat resistant paints flexibility KR-272 50 Xylene Slow Low Medium Heat resistant paints Excellent heat resistance Methyl/Phenyl Type Excellent flexibility and KR-282 50
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