La tecnología de moldeo de silicona es un proceso de fabricación que transforma caucho de silicona liquida (LSR) o compuestos de silicona sólidos en productos con formas de precisión mediante curado controlado. Aprovecha la elasticidad única de la silicona., resistencia al calor, y biocompatibilidad para servir a industrias que van desde la protección de reliquias culturales hasta dispositivos médicos. Pero, ¿qué hace que esta tecnología sea versátil?, how do you select the right methods for specific needs, and how to avoid common production pitfalls?
1. Core Types of Silicone Molding Technology: Un análisis comparativo
La tecnología de moldeado de silicona varía según el estado del material y el mecanismo de curado.. La siguiente tabla desglosa los tipos clave, sus fortalezas, y usos ideales:
| Tipo de tecnología | Características clave | Ventajas | Limitaciones | Escenarios de aplicación ideales |
| Caucho de silicona líquida (LSR) Moldura | Utiliza LSR de dos componentes. (mezclado 1:1 o 10:1); cura a 120-180°C | Alta precisión (± 0.01 mm); sin subproductos; tiempo de ciclo rápido (30–60s/parte) | Alto costo del equipo; Requiere máquinas de inyección especializadas. | Dispositivos médicos (P.EJ., componentes protésicos), productos para bebés (P.EJ., pezones de chupete) |
| Moldeo por compresión de silicona sólida | Utiliza láminas de silicona sólida precortadas.; prensado en moldes (160–200 ° C, 10–20MPa) | Baja inversión en equipos; adecuado para piezas grandes; fácil de escalar | Longer curing time (5–10min/part); lower detail resolution | Focas industriales, juntas automotrices, large craft molds |
| Silicone Coating & Dipping | Applies thin silicone layers via brushing/dipping; cures at room temp or low heat | Espesor uniforme (5–500 μm); adheres to diverse substrates (metal, fabric) | Limited to thin-walled products; slow for thick layers | Electronic component waterproofing, cultural relic protective coatings |
| Vacuum-Assisted Silicone Molding | Uses vacuum chambers to eliminate bubbles during pouring; for LSR or solid compounds | No bubble defects; high surface finish (Ra≤1.6μm) | Longer process time; requires vacuum equipment | Precision jewelry molds, componentes ópticos, cultural relic replication |
2. Material Selection for Silicone Molding: Match to Performance Needs
The success of silicone molding depends on choosing the right silicone type. Below is a guide to material categories and their key parameters:
A. Silicone Material Categories
| Categoría de material | Características clave | Normas de cumplimiento | Casos de uso típicos |
| Silicona de curación de condensación | Releases ethanol during curing; bajo costo; fácil de operar | De grado industrial (no food/medical compliance) | Ordinary crafts, non-critical seals |
| Silicona de curado de adición | No by-products; baja contracción (<0.1%); alta pureza | FDA/ISO 10993 (médico); FDA 21 CFR (alimento) | Medical prosthetics, food-contact molds (P.EJ., chocolate molds) |
| Fluorosilicone | Heat resistance up to 300°C; resistencia química (ácidos, aceites) | MIL-STD-883 (aeroespacial); ASTM D2000 (automotor) | Aerospace seals, high-temperature industrial gaskets |
B. Critical Material Parameters to Consider
- Dureza (Costa a):
- 5–10 °: Ultra-soft (cultural relic cushions, medical skin contact parts)
- 20–30°: Medio (resin craft molds, baby product components)
- 40–60°: Duro (focas industriales, juntas automotrices)
- Viscosidad:
- Bajo (<5,000 CP): Flows into micro-details (jewelry molds, electronic component coatings)
- Alto (>10,000 cP): Ideal for brushing/dipping (thick protective layers for cultural relics)
- Tear Strength:
4KN/M: High-durability needs (reusable molds, frequent-use seals)
- 2–3kN/m: Budget-friendly, low-cycle products (disposable craft molds)
3. Standardized Workflow of Silicone Molding Technology
A typical silicone molding process follows 5 etapas clave, with strict controls at each step to ensure quality:
Escenario 1: Pre-Production Preparation
- Prototipo & Diseño de moldes:
- For uneven substrates (madera, piedra), spray PVA water-soluble release agent to prevent silicone adhesion.
- Agregar cementos (0.5–1 mm) to mold edges to avoid stress concentration and tearing.
- For deep-hole structures, embed magnetic nuts for post-molding positioning.
- Configuración de herramientas:
- Build a containment frame (glass/acrylic) 10cm taller than the prototype’s highest point to prevent overflow.
- Reserve a glue injection port (diameter ≥1cm) and serpentine exhaust grooves to release air.
Escenario 2: Preparación de material & Mezcla
- Component Mixing:
- For LSR: Use an electronic scale to weigh AB components (P.EJ., 1:1 relación) with ±0.1g accuracy.
- For solid silicone: Cut compounds into blanks matching the mold’s cavity volume (add 5–10% for compression shrinkage).
- Defoaming:
- Place mixed LSR in a vacuum chamber (-0.1MPA) for 15–20 minutes; repeat 2–3 times at 5-minute intervals for bubble-free results.
Escenario 3: Moldura & Curación
| Tipo de tecnología | Molding Process | Parámetros de curado |
| LSR Molding | Inject mixed LSR into heated molds (120–150 ° C) via specialized injection machines | Tiempo de cura: 30–60s; presión: 5–10MPa |
| Moldura de compresión | Place solid silicone blanks in molds; apply pressure (10–20MPa) y calor (160–180 ° C) | Tiempo de cura: 5–10min; post-cure at 200°C for 2h to eliminate stress |
| Coating/Dipping | Brush/dip substrate in silicone; let stand for 10–15min to level | Room-temperature cure: 24h; low-heat cure: 60°C for 2h |
Escenario 4: Fundamento & Postprocesamiento
- Fundamento:
- Use thin plastic sheets to separate silicone from molds; tap the back gently to vibrate stuck parts.
- Para moldes complejos, pre-cut guide grooves (depth ≤1/3 of mold thickness) to ease peeling.
- Guarnición & Refinamiento:
- Cut excess flash with sharp scissors; sand inner surfaces with 400–600 grit sandpaper for Ra≤1.6μm smoothness.
Escenario 5: Inspección de calidad
- Estabilidad dimensional: Measure key dimensions 3 times with a caliper; ensure tolerance within ±0.5%.
- Calidad de la superficie: Use a roughness meter to verify Ra≤1.6μm; check for pockmarks or bubbles.
- Performance Testing: For high-cycle products, run dynamic fatigue tests (≥100,000 folds without tearing).
4. Troubleshooting Common Issues in Silicone Molding
Incluso con controles precisos, issues may arise. Below is a cause-and-solution guide for frequent problems:
| Problem Phenomenon | Causa principal | Solución práctica |
| Surface Pockmarks/Imperfections | Substrate contamination (oil/dust); environmental dust adhesion | – Clean prototypes with alcohol; operate in a dust-free workshop.- Apply a thin release agent layer to smooth uneven surfaces. |
| Uneven Thickness | Turbulence from fast pouring; mold cavity design flaws | – Use a funnel for slow, vertido en capas (1–2cm/min).- Optimize mold vents to balance pressure distribution. |
| Bubble Trapping | Inadequate vacuum defoaming; mixing too vigorously | – Extend vacuum time to 20–25min; add a second defoaming cycle.- Stir silicone at 30–50 RPM (avoids air entrapment). |
| Edge Curl | Uneven curing shrinkage; high exotherm during molding | – Switch to low-temperature curing (reduce by 10–15°C).- Add a 2-hour post-cure at 60°C to relieve internal stress. |
| Short Service Life | Resin/chemical residue corrosion; UV aging | – Clean molds with steam + neutral detergent after each use.- Store molds in opaque containers (avoids UV exposure); apply talcum powder for long-term storage. |
5. Industry-Specific Applications of Silicone Molding Technology
Silicone molding technology solves unique challenges across sectors. Here are key use cases with implementation details:
| Industria | Caso | Molding Technology Used | Key Innovations |
| Cultural Relic Protection | Fragile relic support & shape replication | Vacuum-assisted LSR molding (5° Shore A ultra-soft silicone) | Embedded optical fiber sensors to monitor relic stress in real time; glass fiber reinforced layer for durability |
| Dispositivos médicos | Plantillas ortopédicas personalizadas | Moldura LSR de curado por adición (grado biocompatible) | 3Prototipos escaneados en D para un ajuste personalizado; post-curado a 120°C para cumplir con ISO 10993 Normas de biocompatibilidad |
| Fabricación de juguetes | Moldes para muñecas de edición limitada. (piezas multicolores) | Moldeo por compresión modular (silicona coloreada) | Moldes cabeza/cuerpo separados con posicionamiento magnético; Silicona coloreada para una fácil identificación de las piezas. |
| Electrónica | Impermeabilización de placas de circuito | Recubrimiento de silicona (LSR de baja viscosidad) | Revestimiento uniforme de 20 μm; Se cura a 80°C para evitar dañar los componentes electrónicos. |
6. La perspectiva de Yigu Technology sobre la tecnología de moldeo de silicona
En la tecnología yigu, we see silicone molding technology as a bridge between precision engineering and creative needs. For cultural relic protection projects, our vacuum-assisted LSR molding (5° Shore A silicone) has successfully replicated 200+ fragile artifacts, with 0.1mm detail accuracy and real-time stress monitoring. Para clientes médicos, our addition-cure LSR molding process meets FDA 21 CFR standards, delivering custom prosthetic components with <0.01mm dimensional tolerance.
Estamos avanzando en dos innovaciones clave: 1) Developing eco-friendly LSR (reducing VOCs by 35%) for sustainable manufacturing; 2) Integrating AI into mold temperature control (optimizing curing time by 20% manteniendo la calidad). Our goal is to make silicone molding technology more accessible, eficiente, and tailored to industry-specific challenges.
Preguntas frecuentes
- What’s the difference between LSR molding and solid silicone compression molding for medical products?
LSR molding is ideal for high-precision, Piezas médicas pequeñas (P.EJ., consejos de catéter) due to its ±0.01mm tolerance and biocompatibility (sin subproductos). Solid silicone compression molding works for larger parts (P.EJ., orthotic braces) y tiene costos de equipo más bajos pero tiempos de ciclo más largos. Elija siempre LSR de curado por adición para productos médicos implantables/en contacto con la piel.
- Cómo prolongar la vida útil de los moldes de silicona fabricados con esta tecnología?
Clean molds with steam + detergente neutral (Evite herramientas afiladas) después de cada uso; almacenar en opaco, contenedores secos (previene el envejecimiento UV); aplique una fina capa de talco en polvo para guardarlo sobre 1 mes. Para uso de alta frecuencia, añadir un post-curado de 2 horas a 60°C cada 50 ciclos para refrescar la elasticidad.
- ¿Se puede utilizar la tecnología de moldeo de silicona para piezas industriales de alta temperatura? (P.EJ., 250° C+)?
Yes—use fluorosilicone material (heat resistance up to 300°C) with compression molding (180–200°C cure). Ensure a 4-hour post-cure at 220°C to enhance heat resistance. This setup is suitable for aerospace seals and high-temperature industrial gaskets, meeting MIL-STD-883 standards.