Heptamethyltrisiloxane

Basic Product Information

• Product Name: Heptamethyltrisiloxane
• Appearance: Colorless Transparent Liquid

TYPICAL PROPERTIES

Appearance	colorless transparent liquid
purity  (GC),%	>99
Molecular weight	222.5

Physical Properties

• Appearance: Colorless transparent liquid.
• Boiling Point: 165–175°C.
• Volatility: Moderate evaporation rate (completely volatilizes within 3–5 minutes), leaving no residue.

Chemical Properties

• Active Structure: Features reactive Si-O-Si bonds, enabling ultra-low surface tension (18–20 mN/m) for rapid spreading and penetration.
• Key Functionality: Enhances wetting efficiency on hydrophobic surfaces (e.g., plant leaves, plastic substrates).
• Environmental Compliance: Meets EPA standards (U.S. Environmental Protection Agency) and GB 2763 (China’s national standard for pesticide residues in food).
• Classification: Certified as an eco-friendly additive, suitable for applications requiring low environmental impact.

Product Functions

• Deep Penetration, Breaking Crop Surface Barriers

Disrupts Cuticular Wax Layer:

Leverages ultra-low surface tension (18–20 mN/m) to rapidly wet and spread on wax-coated leaves/stems, overcoming hydrophobicity.

Targeted Delivery:

Capillary action penetrates key sites (stomata, leaf veins), boosting systemic pesticide translocation efficiency (+25–40%).

• Rainfastness & Prolonged Efficacy

Film-forming Protection:

Forms a micro-nano mesh film upon drying, firmly adhering to crops to reduce wash-off (rainfastness retention >85%).

Controlled Release:

Slows active ingredient degradation, maintaining efficacy post-rainfall/irrigation (field efficacy retention ≥90%).

• Synergistic Efficiency, Cost Reduction

Enhanced Utilization:

Improves spray coverage uniformity (droplet density +30–50%) and reduces blind spots.

Dosage Reduction:

Cuts pesticide input by 20–30% under equivalent efficacy, aligning with “reduce-use, enhance-efficiency” policies.

• Broad Compatibility

Chemical Stability:

Wide pH tolerance (3–9), inert to common pesticides (e.g., organophosphates, pyrethroids).

Formulation Versatility:

Compatible with EC (emulsifiable concentrate), SC (suspension concentrate), WG (water-dispersible granules).

• Spray Quality Optimization for Aerial Application

Anti-drift:

Reduces droplet surface tension, improves size uniformity (DV50: 150–300 μm), and minimizes drift losses (<5%).

Anti-evaporation:

Slows droplet evaporation in hot/dry conditions, increasing UAV spray deposition rate (+15–25%).

Applications

Crop Types

• Field Crops

Cereals: Rice, wheat, corn, sorghum

Tubers: Potato, sweet potato

Legumes: Soybean, peanut, mung bean

• Cash Crops

Fruit Trees: Citrus, apple, pear, grape, peach

Vegetables: Tomato, cucumber, pepper, eggplant, leafy greens

Industrial Trees: Tea, rubber, oil palm

• Specialty Crops

Medicinal Herbs: Ginseng, Panax notoginseng, goji berry

Floriculture: Rose, chrysanthemum, orchid

Protected Agriculture: Greenhouse vegetables, nursery flowers

Pesticide Types

• Herbicides

Non-selective: Glyphosate, glufosinate

Selective: Pendimethalin, acetochlor

Post-emergent: Quizalofop, nicosulfuron

• Insecticides

Organophosphates: Chlorpyrifos, dichlorvos

Pyrethroids: Lambda-cyhalothrin, bifenthrin

Neonicotinoids: Imidacloprid, thiamethoxam

• Fungicides

Triazoles: Tebuconazole, difenoconazole

Strobilurins: Azoxystrobin, pyraclostrobin

Others: Mancozeb, chlorothalonil

• Plant Growth Regulators

Promoters: Gibberellins, brassinolide

Inhibitors: Paclobutrazol, chlormequat chloride

Core Advantages

Advantage	Agronomic Value	Data Support
Instant Penetration Tech	Spray penetration time reduced to 8–15 seconds	Leaf contact angle ↓ from 85° to 12° (NY/T 1860)
Rainfastness Tech	Efficacy retention >90% after 4h rainfall	Simulated rainfall test (GB/T 8321.10)
Dosage Reduction & Synergy	Chemical cost reduced by 25% per mu	Field trials (Jiangsu rice fields, 2023)
Aerial Application Compatibility	Drift reduced by 40%	UAV spray tests (droplet size <100μm)

Market Value

Market Size & Growth Trends

• Global Market Overview

2023 Market Size: HMTS in pesticide applications valued at USD 180–220 million, accounting for 12–15% of the global pesticide adjuvant market.

Growth Forecast (2024–2030): Projected CAGR 7–9%, reaching USD 300–350 million by 2030.

Key Drivers:

Pesticide reduction policies (e.g., China’s “Double Reduction” initiative, EU Farm to Fork Strategy).

Rising pest/weed resistance requiring high-efficiency penetrants.

Adoption of aerial application (UAV spray), demanding low-surface-tension adjuvants.

Technological Advantages

• Irreplaceable Performance

Ultra-spreading performance: Contact angle <10° (vs. >30° for conventional adjuvants), enabling uniform film formation on leaves.

Hard water tolerance: Stable across pH 4–9, compatible with diverse pesticide formulations.

• Environmental Compliance

Replaces high-risk adjuvants (e.g., nonylphenol ethoxylates/NPEs), compliant with:

China’s Restricted/Banned Pesticide Adjuvant List

EU Regulation (EC) No 1107/2009

Future Growth Opportunities

• Key Expansion Areas

Resistance Management:

HMTS reduces pesticide input by 20–30% amid global herbicide-resistant weeds (>500 species).

Bio-pesticide Synergy:

Acts as a synergist carrier for plant oil-based insecticides (e.g., pyrethrins).

Precision Agriculture:

Integrates with variable-rate spraying to optimize pesticide utilization (field efficiency +15–25%).

Experimental Data & Case Studies

Rice Herbicide Synergy Trial

• Key Data

Glyphosate + 0.2% Heptamethyltrisiloxane:

Weed necrosis accelerated from 7 days → 3 days.

Rainfastness: 88% efficacy retention after 2h rainfall (vs. 52% for conventional formulations).

• Case Example

Heilongjiang Agricultural Reclamation Group:

Applied across 100,000 mu (≈6,667 hectares), reducing weeding costs by 30%.

Awarded provincial Green Agriculture Certification.

Citrus Red Mite Control

• Key Data

Abamectin + 0.3% Adjuvant:

24-hour mite mortality rate increased from 70% → 95%.

Residual efficacy extended to 15 days (vs. 10 days for standard treatment).

• Case Example

Ganzhou Orchard, Jiangxi:

Spray frequency reduced from 4 → 2 times/season.

100% pesticide residue compliance rate in fruits.

Aerial Spray Optimization

• Key Data

Droplet deposition density increased by 35%, drift rate <5% (National Standard: ≤15%).

• Case Example

Wheat Field Unified Control, Henan:

Saved CNY 180,000/season (≈USD 25,000) in UAV spray costs.

Preparation Process, Core Technologies, and Precautions

Preparation Processes

• Hydrolytic Condensation Method

Raw Material Preparation

Primary materials: High-purity trimethylchlorosilane and hexamethyldisiloxane.

Auxiliaries: Catalyst (e.g., concentrated sulfuric acid), solvent (toluene), and neutralizing agent (sodium carbonate).

Quality control: Multi-stage purification and rigorous impurity testing (e.g., residual chloride <50 ppm) to meet pesticide-grade safety standards.

Hydrolysis Reaction

Conditions: Reactor with stirring and reflux systems; low-temperature (0–20°C) environment.

Procedure:

Slowly add trimethylchlorosilane to a water-solvent mixture.

Control dripping rate (<5 mL/min) and reaction temperature to minimize byproducts (e.g., siloxane oligomers).

Output: Trimethylsilanol with >98% conversion efficiency.

Condensation Reaction

Conditions: Temperature 50–80°C, acidic catalysis.

Procedure:

Add hexamethyldisiloxane to trimethylsilanol.

Remove low-boiling byproducts (e.g., HCl) via fractional distillation.

Key metric: Achieve >95% heptamethyltrisiloxane selectivity.

Post-Treatment

Neutralization: Add Na₂CO₃ to pH 6.5–7.5.

Purification:

Water washing (3 cycles) → phase separation → drying (molecular sieves).

Vacuum distillation (10–15 mmHg, 80–100°C) → final purity ≥99.5%.

• Hydrosilylation Method

Raw Material Preparation

Primary materials: Hydrogen-terminated silicone oil, vinyltrimethoxysilane.

Catalyst: Chloroplatinic acid (H₂PtCl₆, 50–100 ppm Pt loading).

Solvent: Isopropanol (HPLC grade, H₂O <0.1%).

Hydrosilylation Reaction

Conditions: Dry nitrogen atmosphere, 80–120°C.

Procedure:

Mix silicone oil and catalyst, then gradually add vinyltrimethoxysilane (molar ratio 1:1.1–1.3).

Monitor exotherm (<5°C/min) to prevent runaway reactions.

Intermediate: α,ω-divinylsiloxane with Si-H conversion >99%.

Hydrolysis & Polycondensation

Hydrolysis: Add deionized water (H₂O:Si-H = 1.2:1 molar) under pH 4–6.

Polycondensation:

Stir at 60°C for 4–6 hours.

Adjust pH to 8–9 for silanol condensation.

Yield: 85–90% heptamethyltrisiloxane.

Post-Treatment

Filtration: Remove Pt catalyst via 0.2 μm membrane.

Distillation: Short-path distillation (150°C, 1 mmHg) → pesticide-grade product.

Core Technologies

• Hydrolytic Condensation Method

Ultra-Purification:

Molecular distillation for trimethylchlorosilane (purity >99.9%).

Adsorption beds (activated carbon + zeolite) for hexamethyldisiloxane.

Reaction Optimization:

PID-controlled jacketed reactors (±0.5°C accuracy).

Online FTIR monitoring of silanol intermediates.

Impurity Control:

Triple-wash protocol (NaHCO₃ → DI water → brine).

Molecular sieve drying (H₂O <50 ppm).

• Hydrosilylation Method

Catalyst Engineering:

Heterogenized Pt catalysts (e.g., Pt/SiO₂) for 5-cycle reuse.

Ligand-modified systems (e.g., Karstedt catalyst) for 98% selectivity.

Process Intensification:

Microreactor technology for precise thermal control.

Real-time GC-MS tracking of byproducts (e.g., methane).

Quality Assurance:

ICP-OES for Pt residue testing (<1 ppb).

ISO 9001-certified batch consistency protocols.

Safety Guidelines

• Incompatibilities:

Avoid strong oxidizers (e.g., KMnO₄, HNO₃) → risk of explosive silane gas.

• Storage:

Amber glass containers at 5–30°C; shelf life 12 months.

• PPE Requirements:

Nitrile gloves + ANSI Z87.1 goggles + Type N95 respirator.

Packaging & Ordering

Packaging: 200kg/1000kg plastic drums (customizable).