I. Basic Properties of Phenyl Silicone and Basics of Building Applications
Phenyl silicone is a special type of silicone rubber that significantly improves its performance by introducing phenyl groups into the siloxane molecular structure. Compared to ordinary silicone, phenyl silicone has the following properties:

High and Low Temperature Resistance: Maintains stable performance within a range of -60°C to 260°C
Weather Resistance: Excellent resistance to UV rays and ozone
Chemical Stability: Excellent resistance to acids, alkalis, and salts
Hydrophobicity: Optimized surface energy (contact angle <90°) reduces moisture penetration
Mechanical Properties: Tensile strength 3.3-17.2 MPa, elongation at break 150%-500%

II. Key Material Performance Requirements for Building Sealing
Building sealing materials must meet the following core performance indicators:
Performance Category                Specific Requirements                                                               Test Standard
Physical Properties:                    Tensile strength ≥ 0.4 MPa, elongation at break ≥ 200%               GB/T 14683-2017
Durability:                                 Performance retention ≥ 80% after aging at 70°C for 168 hours     GB/T 14683-2017
Adhesion:                                 Adhesion retention ≥ 80% after 96 hours of water immersion         GB 16776-2005
Application Performance:            Droop ≤ 3mm, Tack-Free Time ≤ 180 minutes                              GB/T 14683-2017
Environmental Performance:       VOC Emissions ≤ 650g/L (Solvent-Based)                                     GB 50325-2020

III. Performance Advantages of Phenyl Silicone in Building Sealing
Extreme Temperature Adaptability: Compared to ordinary silicone (-50°C to 200°C), phenyl silicone can extend its operating temperature to -60°C to 260°C.
Long-Term Weathering Resistance: No significant degradation after 2000 hours of QUV aging testing.
Chemical Stability: Withstands acid and alkaline environments with a pH range of 2-12.
Mechanical Durability: Compression Set ≤ 15% (ISO 815 standard).
Application Ease: One-component products can be used directly, while two-component products can be applied with a dispensing machine.

IV. Application Selection Guide for Different Building Scenarios
1. Curtain Wall Sealing
Key Performance Features: Weather resistance, displacement capacity (≥±20%), UV resistance
Product Selection: High-phenyl content (10-20%) silicone to ensure self-extinguishing properties
Key Construction Points: Compatibility and adhesion testing are required to avoid three-sided bonding

2. Door and Window Sealing
Key Performance Features: Resilience (Shore A 40-80), mildew resistance
Product Selection: Medium-phenyl content (5-10%) silicone to balance cost and performance
Key Construction Points: Ensure the seal fits the gap and installs securely without gaps

3. Roof Waterproofing
Key Performance Features: Heat resistance (≥90°C), low-temperature flexural strength (-30°C)
Product Selection: High-phenyl content (30%) silicone to enhance radiation resistance
Key Construction Points: Establish two waterproofing lines, with joint widths ≥10mm

V. Performance Comparison with Other Sealing Materials
Performance Indicators:                Phenyl silicone                  Polyurethane                 Polysulfide rubber
Temperature range:                       -60°C to 260°C                 -40~90℃                     -30~80℃
Weather Resistance:                     Excellent (2000h)               Fair (500h)                    Poor (300h)
Chemical Stability:                        Excellent                           Good                            Fair
Service Life:                                 25 years +                        10-15 years                   8-10 years
Cost:                                           High                                  Medium                        Low

VI. Construction Process and Acceptance Criteria
1. Construction Process
Joint Preparation: Remove dust and oil stains. Width deviation ≤ 20%
Primer Treatment: Apply a special primer to strengthen the substrate surface
Filling and Sealing: Single-component direct filling, two-component requires mixing in a glue mixer
Surface Finishing: Use specialized tools to ensure smooth and aesthetically pleasing joints

2. Acceptance Criteria
Physical Properties: Tensile Strength ≥ 0.6 MPa, Elongation at Break ≥ 100%
Durability: Performance Retention after Thermal Aging ≥ 80%
Adhesion: Cohesive Failure Area within the Adhesive Layer ≥ 80%
Appearance Quality: No Bubbles, Cracks, or Significant Depressions

VIII. Selection Recommendations and Precautions
Phenyl Content Selection:
Normal Environments: 5-10% Low Phenyl
High Temperature/Radiation Environments: 10-30% High Phenyl