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Posts tagged with “CPSIA ISO 17025 ILAC MRA Accredited Laboratory”

Polyester Fiber And Triexta Fiber Generic Subclass Testing Capability Enhanced

Using a combination of analytical techniques as well as experience with weft knit, warp knit, woven and non woven textile structures, Vartest provides a unique capability for analyzing polyester fiber and the polymers which make them up including FTC designated polyester fiber subclasses and related fibers.


Micro FTIR Analysis Allows Molecular Structure Analysis Of Single Fibers And Filaments

Preparing Vartest's FTIR Microscope For Textile Fiber Work With Liquid Nitrogen


The Federal Trade Commission covers but is not limited to three related polyester polymers used to produce textile fibers: Polyethylene terephthalate (often abbreviated as PET and the polymer which makes up the world’s most commonly used textile fiber), polytrimethylene terephthalate (FTC generic sub class triexta and also commonly known as PTT and with the current IUPAC name poly(propyleneterephthalate) and polybutylene terephthalate (often abreviated as PBT). The structures of PET, PTT and PBT are shown in the following ball and stick models:
Polyester Polymer Chains Modeled With Chem Bio 3D Ultra

Three Repeat Unit Chains Of Polyethyleneterephthalate, Polytrimethyleneterephthalate and Polybutyleneterephthalate


Fibers made of PTT may be labelled “Triexta” however fibers composed of PBT do not have an FTC designated subclass and so can be labeled “Polyester” and be more fully characterized as PBT Polyester. Fibers made of PET are usually simply labeled as “Polyester”.
The chief difference in chemical structure between these three polymer groups is the addition of a single methyl group to the polymer repeat with each of PTT and PBT. PET has two methyl groups in the hydrocarbon chain connecting phthalate esters, PTT three and PBT four. The addition of methyl groups leads to significant changes in fiber performance in end use, making PTT for example, particularly suited to end uses such as carpeting. The addition of methyl groups to the hydrocarbon chain also leads to decreasing melt point as seen in the following differential scanning calorimetry curves:


PET, PTT and PBT compared

Differential Scanning Calorimetry Comparison Of PET, PTT and PBT

Micro Fourier transform infrared analysis helps to differentiate these polymer groups with clear separation of PBT, PTT and PET capable with even a single fiber and enabeling dissected filament yarns from a complicated structure such as a multi bar tricot warp knit to be positively identified both qualitatively and quantitatively as seen in the following light micrograph:
Triexta (PBT) and conventional textile polyester (PET) dissected from a two bar tricot warp knit fabric.
Once dissected micro FTIR spectra of the yarns above are obtained and run against a search library for identification. The image above shows the dissected PET top bar yarn of a 1-0/2-3 fully threaded tricot structure as well as the PBT 1-2/1-0 back bar. A micro Fourier transform infra red analysis of SmartStrand carpet fiber is shown below with a 95% Euclidean hit to a control sample of known triexta fiber:
Eulidean Library Search For Triexta

Micro Fourier Transform Infra Red Analysis Of SmartStrand Triexta Fiber

Nuclear magnetic resonance (NMR) testing complements this work differentiating between PET, PTT and PBT as seen in the following Hydrogen-1 NMR and Carbon-13 NMR comparison done at 300 megahertz with deuterated trifluoroacetic acid as the solvent:
Comparison Of PET, PTT and PBT

300 Megahertz Nuclear Magnetic Resonance Spectra

Polyester Comparison Via FTIR

300 Megahertz Nuclear Magnetic Resonance Spectra

Vartest provides in depth analysis of all characteristics of fiber make up, morphology and performance assisted by a proprietary search library of thousands of fibers from all markets and end uses.



Announcing service expansions & equipment updates

Vartest Laboratories continues to expand services for flammability, textile insulation and vapor resistance to facilitate performance assessment of safety and protective products and garments.

Vartest Laboratories demonstrates excellence in services provided to high technology and compliance markets, while maintaining unsurpassed breadth of methods and capabilities to the textile, apparel, home textile, and industrial markets, and military sectors. We are continually improving our offerings through investment in the latest technology and ISO-17025 accredited operations.

Recent additions and updates to the laboratories included:

  • Installation of new instruments for Thermal and Radiant Protective Performance (TPP & RPP) to meet ISO, EN, NFPA, ANSI and military requirements.
  • Updating of basic instruments for ASTM 6413 and NFPA 701 flammability testing.
  • Isothermal Sweating Hot Plate instrumentation along with a broad scope environmental chamber and remote access technology.
  • Our GCMS section is also supported by high performance microwave digestion and rotary evaporation instruments.
  • Near Infra Red Spectrophotometry for measurement of spectral reflectance.
  • Updated hydrostatic penetration capability.
  • Running all methods all methods including ASTM D751.
  • IL options ISO 811, AATCC 127 and others up to 200,000 millimeters of water pressure.

With this expanded capability, Vartest provides highly specialized protective performance assessment of products and applications related to development and production of fabrications dedicated to military, active sportswear and other specialized markets, which require elevated performance in unique environments.

Vartest sets itself apart with in-house testing using a fully automated large scale goniometric range for evaluation of high visibility trims, including all treatments required by ANSI 107, 207, EN 471 and CSA 96 protocols. It is this dedication and continued investment that positions Vartest as the undisputed leader in color measurement and spectral data in .qtx format, high visibility assessment and third party certification and compliance verification of high visibility safety and protective products and garments.

We invite your enquires and look forward to meeting all of your company’s testing requirements and greatly appreciate the opportunity to do so.