High-performance natural latex emulsion

Yulex maintains its position as the only company to source crude rubber latex from FSC certified plantations, refine and purify using the Yulex Pure process which selects, detaches, and removes unwanted contaminates and proteins. All Yulex products start as refined and purified latex emulsion natural rubber.

Yulex produces FSC 100%-certified latex emulsion natural rubber, a vital raw ingredient in thousands of products under the Yulex Pure® brand name. Yulex Pure latex Eemulsion is the industry’s only pure brand of natural rubber latex emulsion and the only latex emulsion that does not use harsh and damaging chemicals to mask harmful allergens and proteins. Yulex Pure® latex emulsion natural rubber is refined and purified using the proprietary Yulex Pure process which removes excess and unwanted impurities, allergens and proteins in a safe, chemical-free and sustainable method. Yulex Pure latex emulsion is sourced only from Forest Stewardship Council (FSC) 100% certified plantations and is used to produce Yulex Pure dry solid natural rubber.

Yulex Pure® latex emulsion is a direct replacement for any manufacturing process currently utilizing crude hevea latex. Yulex Pure® latex emulsion can be used to produce dipped products such as medical examination and surgical gloves, work and utility gloves, fabric coatings, medical devices such as heart catheters, condoms, urinary catheters, and elastic tubing, toy balloons, infant and children’s toys, and to produce open cell foams for mattresses, pillows and mattress toppers, seating cushions, and as the key polymer in adhesives and glues – to name just a few.

Yulex Pure latex emulsion specifications and packaging options are available from Yulex customer service.

beaker with latex emulsion

Yulex Pure latex emulsion is available in traditional high ammonia (HA) version and low ammonia (LA) version. Non-ammonia versions are available upon special request.

The Advantages of Yulex Pure Latex Emulsion

  • Significantly reduced protein levels – helping to improve product safety

  • Purity means a bright white color – helping to reduce extra compound colorants

  • Purity reduces bacterial loading – improves and extends compounded pot-life by 75%

  • Purity eliminates unwanted contaminates – increases elongation, tensile and green strength

  • Purity reduces odor-causing pollutants common in crude hevea rubber

  • FSC 100% ensures ongoing sustainability of vital forested lands globally


Yulex Pure is a GRAS material and meets ASTM D1076 Category 4 material for the total protein content. It is a high performance cis-1,4-polyisoprene plant based backbone material. Yulex Pure is ultra-high purity with over 99.9% of impurities removed. It can be stabilized and compounded with a variety of formulas depending on the end user application:

  • plus ammonia
  • plus ammonia and K laurate
  • plus ammonia and K oleate
  • plus ammonia, surfactant and flame suppressant

Potential applications include dip formed, sheeted, coated, sprayed, foamed, and adhesive products. Lexcell Pure emulsion achieves high tensile strengths in combination of high elongations and low modulus. Typical compounding techniques such as sulfur vulcanization and peroxide cure can be used. Material readily accepts common compounding additives used in both natural and synthetic polyisoprene systems such as: mineral fillers, process fluids, antidegradants, colorants, fragrances and physical property modifiers.


Yulex Pure is available for purchase in 5-gallon pails, 55 gallon coated steel drums, 1 MT (wet) IBC, or 20 MT (wet) bladders.


Store Lexcell Pure in original unopened container at 20°C ± 5°C (59-77°F) and out of direct sunlight. Product should not be frozen. Storage conditions, changes in pH, and contamination can all have a significant impact on the actual shelf life of material. Once opened it is recommended to monitor material through visual inspection and pH readings to help determine impact of storage. For IBC loads, the material should be stirred at low speeds every three to five days for one hour. Drums should be fully inverted once a week. Refrigerated storage can help maximize shelf life once opened.

* Storage conditions, changes in pH, and contamination can all have a significant impact on the actual shelf life of material.

Physical Properties & Performance Characteristics

Property Typical Values
Total Solids Content 60% to 63%
Dry Rubber Content 60% to 63%
Non-rubber Content < 0.1% difference between %TSC and %DRC
pH 10 to 12
Alkalinity (as ammonia, % Latex) 0.4 to 0.6
Total Protein Content ≤ 100 ug/ g Latex
Coagulum ≤ 0.03%
MST (@55% TSC)** >700 sec
Color Bright White for Lexcell Pure and Light to Medium Gray for Lexcell Pure FS
Odor Slight Ammonia
Elongation %* 50 to 1550
Tensile* 10 – 40 MPa
Modulus* 1.2 to > 10
Foam Density* 0.05 to 0.3 for Lexcell Pure FS; and 0.1 to 0.5 for Lexcell Pure FS
Compression Set* Good to Excellent
UV/ Ozone* Fair to Excellent
Tear* Good to Excellent
Abrasion* Good to Excellent
Chemical Resistance* Good to Excellent
Water Absorbency Good to Excellent

* Features are compound and process dependent

** MST can be modified by additions of surfactants by the preference of the end user


  • Plant Based
  • Total Protein Levels
  • Ultra Pure
  • GRAS Approved
  • FDA Compliant Material
  • **Flame Suppressant
  • Overall Performance Properties
  • Total Solids Content
  • Dry Rubber Content (Purity)
  • Material Purity Level
  • Material Consistency
  • *Elongation %
  • *Tensile
  • *Modulus
  • Color
  • Color – Air Dried Film
  • Raw Material Biodegradable
  • Green Strength

Latex Emulsion

  • <100 μg/g emulsion
  • Excellent
  • 62%
  • 62%
  • Excellent
  • Excellent
  • 50 to 1550
  • 10 to 40 MPa
  • 1.5 to >10 MPa @ 500%
  • Bright White
  • Crystal Clear
  • Excellent

Commercial Hevea

  • >10,000 μg/g rubber
  • Good
  • 50% to 62%
  • 58% to 60%
  • Poor-Fair
  • Seasonal
  • 50 to 1200
  • 10 to 35 MPa
  • 2.7 to >10
  • Varies
  • Yellowish
  • Good

Synthetic Polyisoprene

  • N/A
  • Varies
  • Varies
  • Varies
  • Varies
  • Excellent
  • Brand Dependent
  • 50 to 1100
  • 10 to 32 MPa
  • 2.5 to >10
  • Varies
  • Varies
  • Fair

*Properties are compound and process dependent
**In Yulex Pure™ FS option

The following information is supplied as general guidelines for the proper disposal of unused Yulex Emulsions or Solids which have not been further compounded or processed. All un‐compounded Yulex emulsions and solids are made from a natural polymer (polyisoprene), and are GRAS and non‐hazardous. Since state and local guidelines vary on regulations for disposal of various materials, it is extremely important that a local waste service provider be consulted on the proper disposal of any material.

Yulex Emulsions: Any non‐compounded emulsion material should be coagulated before disposal. This can be done by simply placing the material in a container in a freezer until all the emulsion has turned into a solid block. The time frame for this will depend on the amount of material being coagulated. Dispose of the material following all local regulations for the disposal of non‐hazardous waste.

Yulex Solids: Any un‐compounded solid material can simply be bagged and disposed of following all local regulations for the disposal of non‐hazardous waste.
Compounded Materials: Both emulsions and solids which have had compounding chemicals added must be handled in accordance to all local regulations for waste disposal. It is the responsibility of the disposer to contact a local waste service to help determine if the materials added are considered potentially hazardous.

If in doubt, always contact a local waste service for consulting on the proper procedures for handling of waste following all local regulations.

Emulsion Results

ASTM D5712 tests for the total aqueous extractable protein and ASTM D6499 is the immunological measurement of antigenic protein.

Material ASTM D5712*
(Total Protein Typical Values)
μg/g Latex
ASTM D6499*
(Antigenic Protein Typical Values)
μg/g Latex
Yulex Pure Emulsion 30-50 ≤10
Commercial Hevea >10,000 μg/g rubber >200 μg/g rubber

* In-House specification for the Emulsion is currently set at ≤100 µg/g Latexx for the Total Aqueous Extractable Protein and ≤15 µg/g Latex for the Immunological Measurement of Antigenic Protein. Results from in-house testing.

Effective Date: 8/28/15


Yulex Natural Rubber Emulsion

beakers with rubber

Yulex Natural Rubber Solid

rubber bricks

YULEX® CC Closed Cell Foam

closed cell foam layers

YULEX® OC Open Cell Foam

open cell foam sample
Photo credit: Tim Davis