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Send EmailStandard Thai Rubber, Technically Specified Rubber, STR, STR 5, STR 10, STR 20, TSR, 9006-04-6
Standard Thai Rubber / STR / STR 5 / STR 10 / STR 20 / Technically Specified Rubber / TSR
CAS Number: 9006-04-6
EINECS: 232-674-7
| Parameter | Description |
|---|---|
| Product Name | Standard Thai Rubber (STR) |
| Other Names | TSR (Technically Specified Rubber), Thai Rubber, Natural Rubber (NR) |
| CAS Number | 9006-04-6 |
| EINECS | 232-674-7 |
| Chemical Formula | (C₅H₈)ₙ |
| Molecular Weight | Variable (depends on degree of polymerization) |
| Chemical Class | Natural rubber (polyisoprene) |
| Appearance | White to pale yellow solid block (bale) |
| Odor | Characteristic rubber odor |
| Density | 0.92 - 0.94 g/cm³ |
| Glass Transition Temperature (Tg) | ~ -70°C |
Standard Thai Rubber (STR) is a technically specified natural rubber (TSR) produced in Thailand according to international standards (ISO 2000:2014, Thai Industrial Standards Institute - TISI). Thailand is the world's largest producer of natural rubber, and STR grades are among the most widely traded natural rubber grades globally. STR grades are classified based on technical specifications including dirt content, ash content, nitrogen content, volatile matter, plasticity, and Plasticity Retention Index (PRI). The grading system follows the TSR (Technically Specified Rubber) convention. STR grades range from high-quality, low-contamination grades (STR 5) to standard, cost-effective grades (STR 20). The main STR grades are STR 5, STR 10, and STR 20, which correspond to SMR 5/10/20, SVR 3L/10/20, and SIR 5/10/20 grades from other producing countries.
| Grade | Quality Level | Dirt Content (max) | Ash Content (max) | Nitrogen Content (max) | Volatile Matter (max) | Po (min) | PRI (min) | Primary Applications |
|---|---|---|---|---|---|---|---|---|
| STR 5 | High Quality | 0.05% | 0.60% | 0.60% | 0.80% | 30 | 60 | High-performance tires, aircraft tires, specialty industrial rubber |
| STR 10 | Medium Quality | 0.08% | 0.75% | 0.60% | 0.80% | 30 | 50 | General automotive tires, industrial rubber products |
| STR 20 | Standard Quality | 0.16% | 1.00% | 0.60% | 0.80% | 30 | 40 | Cost-effective tires, general-purpose rubber products |
Grade Definitions:
STR 5 (High Quality): Highest quality grade with very low dirt content (0.05%) and low ash content (0.60%). Used in premium tire applications, aircraft tires, high-performance products, and applications requiring high purity and consistency. PRI value of 60 indicates good aging resistance.
STR 10 (Medium Quality): Medium quality grade with dirt content (0.08%) and ash content (0.75%). Used in general automotive tires, industrial rubber products, and applications where a balance of quality and cost is required. PRI value of 50 indicates good aging resistance.
STR 20 (Standard Quality): Standard quality grade with higher dirt (0.16%) and ash (1.00%) content. Most commonly used and cost-effective grade. Used in tires, industrial products, and general rubber goods where cost is a primary consideration. PRI value of 40 indicates moderate aging resistance.
Detailed Quality Parameters by Grade:
| Parameter | Unit | STR 5 | STR 10 | STR 20 |
|---|---|---|---|---|
| Dirt Content (max) | % wt | 0.05 | 0.08 | 0.16 |
| Ash Content (max) | % wt | 0.60 | 0.75 | 1.00 |
| Nitrogen Content (max) | % wt | 0.60 | 0.60 | 0.60 |
| Volatile Matter (max) | % wt | 0.80 | 0.80 | 0.80 |
| Initial Plasticity (Po, min) | - | 30 | 30 | 30 |
| PRI (min) | - | 60 | 50 | 40 |
| Mooney Viscosity (ML 1+4 at 100°C) | MU | Variable | Variable | Variable |
Explanation of Key Parameters:
Dirt Content: Impurities such as sand, bark, and foreign matter. Lower is better for premium applications. STR 5 has the lowest dirt content (0.05%).
Ash Content: Inorganic residue after combustion. Indicates mineral contamination. STR 5 has the lowest ash content (0.60%).
Nitrogen Content: Protein content indicator. Higher nitrogen may affect aging resistance. All STR grades have a maximum of 0.60%.
Volatile Matter: Moisture and volatiles. High levels can cause porosity in finished products. All STR grades have a maximum of 0.80%.
Initial Plasticity (Po): Measure of raw rubber's ability to deform under pressure. All STR grades have a minimum of 30.
PRI (Plasticity Retention Index): Resistance to oxidation and aging. Higher PRI indicates better durability. STR 5 has PRI of 60, STR 10 has PRI of 50, and STR 20 has PRI of 40.
| Property | STR 5 | STR 10 | STR 20 |
|---|---|---|---|
| Quality Level | High | Medium | Standard |
| Dirt Content | Very Low (0.05%) | Low (0.08%) | Medium (0.16%) |
| Ash Content | Low (0.60%) | Medium (0.75%) | Higher (1.00%) |
| PRI | Excellent (60) | Good (50) | Moderate (40) |
| Color | Light | Light to variable | Variable |
| Price | Highest | Moderate | Lowest |
| Primary Applications | High-performance tires, aircraft tires, specialty products | General automotive tires, industrial products | Cost-effective tires, general-purpose products |
| Grade | Origin | Characteristics | Equivalence |
|---|---|---|---|
| STR 5 | Thailand | Low dirt, high quality | Comparable to SMR 5 / SVR 3L / SIR 5 |
| STR 10 | Thailand | Medium quality | Comparable to SMR 10 / SVR 10 / SIR 10 |
| STR 20 | Thailand | Standard quality | Comparable to SMR 20 / SVR 20 / SIR 20 |
| RSS 3 | Thailand | Ribbed smoked sheet | Visual grade, high quality |
| SMR 20 | Malaysia | Standard TSR | Comparable to STR 20 |
| SVR 20 | Vietnam | Standard TSR | Comparable to STR 20 |
| SIR 20 | Indonesia | Standard TSR | Comparable to STR 20 |
TSR Naming Convention: The letters indicate country of origin (STR = Thailand, SMR = Malaysia, SVR = Vietnam, SIR = Indonesia), and the number indicates the grade.
| Property | Value |
|---|---|
| Appearance | White to pale yellow solid bales |
| Odor | Characteristic rubber odor |
| Density | 0.92 - 0.94 g/cm³ |
| Glass Transition Temperature | ~ -70°C |
| Mooney Viscosity (ML 1+4 at 100°C) | Variable (grade dependent) |
| Color | Light to variable (higher grades are lighter) |
| Service Temperature Range | -50°C to +100°C |
| Application | Recommended Grade |
|---|---|
| Aircraft Tires | STR 5 |
| High-Performance Passenger Tires | STR 5, STR 10 |
| Truck and Bus Tires | STR 10 |
| OTR (Mining/Construction) Tires | STR 20 |
| Passenger Car Tires | STR 10, STR 20 |
| Retreading | STR 5, STR 10 |
| Application | Recommended Grade |
|---|---|
| Automotive Seals and Gaskets | STR 5, STR 10 |
| Hoses and Tubing | STR 10, STR 20 |
| Conveyor Belts | STR 10 |
| V-Belts and Drive Belts | STR 5, STR 10 |
| Anti-Vibration Mounts | STR 10 |
| Rubber Rollers | STR 5 |
| Application | Recommended Grade |
|---|---|
| Shoe Soles | STR 10 |
| Athletic Footwear | STR 5, STR 10 |
| Rubber Bands | STR 10 |
| Floor Mats | STR 20 |
| Toys | STR 10, STR 20 |
| Application | Recommended Grade |
|---|---|
| Medical Rubber Products | STR 5 |
| Light-colored Products | STR 5 |
| Adhesive Tapes | STR 5, STR 10 |
| Packaging Option | Details |
|---|---|
| Bale Weight | 33.33 kg or 35 kg |
| Bale Dimensions | ~70 cm x 35 cm x 18 cm |
| Pallet Configuration | 36 bales/pallet = 1.26 MT |
| Pallet Type | Wooden pallet, shrink-wrapped |
| Container Capacity (20-ft) | 16 pallets = 20.16 MT |
| Container Type | Standard 20-ft container |
| Parameter | Information |
|---|---|
| Storage Conditions | Cool, dry, well-ventilated area; away from direct sunlight |
| Recommended Temperature | Below 30°C |
| Humidity | Avoid high humidity to prevent mold growth |
| Shelf Life | 12-24 months under proper storage conditions |
| Handling | Avoid contamination with oils, solvents, and dirt |
| Protection | Keep bales covered and protected from moisture and dust |
| Stacking | Maximum 4-5 pallets high for stable storage |
| Parameter | Information |
|---|---|
| Toxicity | Non-toxic |
| Skin Irritation | Non-irritant |
| Eye Irritation | Mild irritant (dust) |
| Inhalation | May cause respiratory irritation (dust) |
| Flammability | Combustible (can burn) |
| Fire Extinguishing Media | Water spray, foam, CO₂, dry chemical powder |
| Special Hazards | Burning produces toxic fumes (CO, CO₂, SO₂) |
| Exposure Route | Action |
|---|---|
| Inhalation | Move person to fresh air. If irritation persists, seek medical attention. |
| Skin Contact | Wash with soap and water. Remove contaminated clothing. |
| Eye Contact | Rinse with plenty of water for at least 15 minutes. Seek medical attention if irritation persists. |
| Ingestion | Rinse mouth. Do NOT induce vomiting. Seek medical attention if large amounts are swallowed. |
| Region | Status |
|---|---|
| EU | REACH registered |
| Turkey (KKDİK) | Mandatory compliance; requires registration |
| USA (TSCA) | Listed |
| Canada (DSL) | Listed |
| Australia (AICS) | Listed |
| Japan (ENCS) | Listed |
| Korea (KECL) | Listed |
| China (IECSC) | Listed |
Regulatory Status:
| Status | Information |
|---|---|
| HS Code | 40012200 (Technically Specified Natural Rubber) |
| CAS Number | 9006-04-6 |
| EINECS | 232-674-7 |
| IARC Classification | Not classified |
| WGK Germany | 1 (slight hazard to water) |
| Category | Names / Identifiers |
|---|---|
| Product Names | Standard Thai Rubber, STR, Thai Rubber, Natural Rubber |
| Grade Names | STR 5, STR 10, STR 20 |
| Common Names | TSR (Technically Specified Rubber), NR |
| Country Equivalents | STR (Thailand), SMR (Malaysia), SVR (Vietnam), SIR (Indonesia) |
Database Identifiers:
| Database | Identifier |
|---|---|
| CAS | 9006-04-6 |
| EINECS | 232-674-7 |
| HS Code | 40012200 |
| Grade Material | HS Code |
|---|---|
| STR 5 | 4001.2210 / 4001.2220 |
| STR 10 | 4001.2210 / 4001.2220 |
| STR 20 | 4001.2210 / 4001.2220 |
| Parameter | Test Method | Significance |
|---|---|---|
| Dirt Content | Sieve Analysis | Purity level; impacts surface finish and processing |
| Ash Content | Ignition | Inorganic contamination |
| Nitrogen Content | Kjeldahl Method | Protein content; affects aging |
| Volatile Matter | Oven Drying | Moisture content; affects processability |
| Initial Plasticity (Po) | Plastimeter | Raw rubber processability |
| PRI | Accelerated Aging | Oxidative stability; service life indicator |
| Mooney Viscosity | Mooney Viscometer | Processing consistency |
| Application | Recommended Grade |
|---|---|
| High-performance tires, aircraft tires | STR 5 |
| General automotive tires | STR 10 |
| Cost-effective tires, general products | STR 20 |
| Industrial rubber products | STR 10 |
| Specialty applications requiring high purity | STR 5 |
| Footwear and consumer goods | STR 10, STR 20 |
| Light-colored rubber products | STR 5 |
| Industry | Applications | Recommended Grade | Suitability |
|---|---|---|---|
| Tire Industry | Aircraft, high-performance, truck tires | STR 5, STR 10 | High |
| Tire Industry | General passenger, OTR tires | STR 10, STR 20 | High |
| Industrial Products | Seals, hoses, conveyor belts | STR 10 | High |
| Footwear | Shoe soles, athletic footwear | STR 5, STR 10 | High |
| Specialty | Medical products, light-colored goods | STR 5 | High |
| Consumer | Rubber bands, mats, toys | STR 10, STR 20 | High |
STR is produced from natural rubber latex through a standardized process:
Latex Collection: Latex is tapped from Hevea brasiliensis trees.
Coagulation: Latex is coagulated using formic acid or acetic acid.
Milling: Coagulum is milled to remove water and impurities.
Drying: Rubber is dried in hot air ovens.
Baling: Dried rubber is compressed into bales.
Grading: Bales are graded based on technical specifications.
| Advantages | Limitations |
|---|---|
| Technically specified (consistent quality) | Poor ozone resistance |
| Standardized specifications ensure consistency | Poor oil and fuel resistance |
| Wide range of grades for different applications | Susceptible to oxidation at high temperatures |
| Good mechanical properties | Requires proper storage to prevent mold growth |
| Competitive pricing (especially STR 20) | Lower grades have darker color |
| Widely accepted in international markets |
SUMMARY:
Standard Thai Rubber (STR) is a technically specified natural rubber produced in Thailand according to international standards (ISO 2000:2014). The main grades are STR 5 (high quality, low dirt content 0.05%), STR 10 (medium quality, dirt content 0.08%), and STR 20 (standard quality, dirt content 0.16%). STR 5 offers the highest purity and aging resistance (PRI 60), used in high-performance tires and specialty applications. STR 10 is used in general automotive tires and industrial rubber products. STR 20 is the most cost-effective grade, used in general-purpose tires and rubber products. Thailand is the world's largest producer of natural rubber. STR grades are comparable to SMR, SVR, and SIR grades from other producing countries. Packaging: 33.33 kg or 35 kg bales, 36 bales/pallet (1.26 MT), 16 pallets/20-ft container (20.16 MT). HS Code: 40012200.
Key Properties:
| Property | Value |
|---|---|
| Appearance | White to pale yellow solid bales |
| CAS Number | 9006-04-6 |
| Density | 0.92 - 0.94 g/cm³ |
| Primary Grades | STR 5, STR 10, STR 20 |
| Primary Use | Tires, industrial products, footwear |
Major Application Areas:
| Industry | Applications |
|---|---|
| Tire Industry | Aircraft, high-performance, passenger, truck tires |
| Industrial Products | Seals, hoses, conveyor belts |
| Footwear | Shoe soles |
| Specialty | Medical products, light-colored goods |
| Consumer | Rubber bands, mats, toys |
Key Safety Points:
NON-TOXIC: Generally safe for handling
COMBUSTIBLE: Can burn; keep away from ignition sources
STORAGE: Store in cool, dry, well-ventilated area; avoid direct sunlight and high humidity
PPE RECOMMENDED: Dust mask, safety goggles, protective gloves (for handling)
PROTECT: Keep away from oils, solvents, and contaminants
CRITICAL WARNINGS:
STR grades are classified by technical specifications (dirt content, ash content, PRI) rather than visual inspection, ensuring consistent quality.
STR 5 is the highest quality grade with the lowest dirt content (0.05%) and highest PRI (60), used in high-performance and aircraft tires.
STR 10 is a medium quality grade (dirt 0.08%, PRI 50) used in general automotive tires and industrial rubber products.
STR 20 is the most common and cost-effective grade (dirt 0.16%, PRI 40), used in general-purpose tires and rubber products.
Thailand is the world's largest producer of natural rubber, and STR grades are among the most widely traded natural rubber grades globally.
PRI indicates aging resistance; higher values (60 for STR 5) indicate better durability and longer service life.
Store away from direct sunlight and heat sources to prevent degradation and maintain quality.
Contamination with oils or solvents can significantly affect rubber performance.
Important Disclaimer: This Technical Data Sheet (TDS) is for informational purposes only. The information provided is based on available data and is believed to be accurate. However, the user is solely responsible for determining the suitability of the product for their specific application and for complying with all applicable regulations and safety requirements. For complete safety, handling, storage, and regulatory compliance information, always refer to the official Safety Data Sheet (SDS/MSDS) provided by the manufacturer/supplier.