Is flex-foam biodegradable? (13 ingredients of flex foam pads)

This article shall look into the biodegradability of flex foam.

It shall also cover other areas such as:

  • Components of flex foam pads.
  • Purpose of each component.
  • Other applications of the components.
  • Toxicity of the flex foam.

Is flex-foam biodegradable?

No, flex foam is not biodegradable. Although this question of its biodegradability will divide opinion, looking at the ingredients label makes one wonder whether the foam is biodegradable.

The foam contains biodegradable materials such as cotton and alcoholic molecules but the majority of flex foam ingredients are non-biodegradable.

What is biodegradation?

Biodegradation is the process by which naturally occurring organic materials are broken down by microorganisms such as bacteria and fungi into small particles which are not harmful to the environment.

Biodegradation is carried out by different agents such as UV radiation, light, wind, and water but the most effective agents of biodegradation are bacteria and fungi.

Biodegradation occurs in three distinct stages: biodeterioration, bio-fragmentation, and assimilation.

The biodeterioration process loosens up the structure of the organic substance. For instance, the cell wall of plants is weakened by light, wind, water, and UV radiation.

Bio-fragmentation involves the breakdown of organic matter into smaller, nontoxic particles by bacteria and fungi, releasing water and carbon dioxide in the process.

Assimilation is the last stage of biodegradation and it involves the microorganisms taking up the products of bio-fragmentation into their biological machinery to be used to make energy.

Biodegradation can either involve the microorganisms using oxygen, aerobic biodegradation or it can involve the microorganisms which do not use oxygen, anaerobic biodegradation.

Aerobic biodegradation breaks down organic matter into small biomass, producing carbon dioxide and water.

Anaerobic biodegradation breaks down organic matter into small biomass and in the process carbon dioxide and methane gases are produced.

Aerobic biodegradation occurs at a faster rate than anaerobic biodegradation whereas anaerobic respiration is more efficient and produces more gases and other products.

What is flex-foam?

Flex foam is a type of sanitary pad from the ‘ALWAYS’ group. There are different types of flex foam sanitary pads made up of different components.

 Flex foam materials are made up of the following ingredients.

  • Polyacrylate foam.
  • Cotton.
  • Hot melt adhesive.
  • Polyethylene.
  • Polypropylene.
  • Calcium chloride.
  • Titanium oxide.
  • Petrolatum.
  • Behenyl alcohol.
  • Zinc oxide.
  • Fragrance.
  • Pigment red 57:1.
  • Pigment Blue 15.
  • Ditallowethyl hydroxyethylmonium methosulfate.

Polyacrylate foam.

This is used as a two-layer that absorbs and locks away fluids.

The foam is acquired from plastic acrylate monomers. The monomers are transparent, elastic, and have big resistance to breakage.

It is used in cosmetic products and sanitary pads as rheology modifiers and film former.


This is an organic fiber that is used to absorb fluid in the sanitary pads.

Cotton is made largely from cellulose, waxes, water, pectins, and mineral salts.

Cotton is soft, fluffy, and sponge-like, properties that help it absorb fluids in sanitary pads.

Hot melt adhesives.

This is a type of glue that is used in sanitary pads to hold the different layers of the pads together.

The glue is also applied to help the pad stick to the underwear.


This is a synthetic plastic fiber that is used to make layers in sanitary pads. Because of its flexible nature, it is used to increase the flexibility of flex foam pads.

The plastic polymer has the following properties.

  • It is inert.
  • It is a strong and highly durable material.
  • It is resistant to microbial degradation.
  • It is lightweight and therefore easy to carry.
  • It is fully recyclable


This is a synthetic plastic fiber that protects the flex foam pads by maintaining their structure.

Polypropylene is also called polypropene.

It is a rigid, semi-crystalline thermoplastic polymer of propene hydrocarbon.

It has almost the same properties and appearance as polyester.

Polypropylene contains the following properties.

  • It is semi-crystalline.
  • It is slightly harder than polyester.
  • It has more tensile strength than polyester.
  • It has high chemical resistance.
  • It is heat resistant.
  • It is resistant to microbial degradation.

Calcium chloride.

Calcium chloride is a salt that is added to flex-foam sanitary pads to absorb the fluid from the body.

It has a high absorption rate and therefore absorbs high amounts of fluids.

Titanium oxide.

This is used in the sanitary pads to make them opaque. 

The particles of titanium dioxide are not absorbed by the body hence it is safe to use. It has a broad-spectrum activity

It is also a common ingredient for sunscreens and other skin protectors because it always reflects the UV radiation, protecting the skin.

Zinc oxide.

It works almost the same way as titanium dioxide. It helps in making the flex foam opaque.

When used in sunscreens and other cosmetic products, it protects the skin from ultraviolet radiation by either absorption or reflection.

It has a broad spectrum and its particles are not absorbed by the body.


Petrolatum is also called petroleum jelly, it is obtained from petroleum.

This is added to the sanitary pad lotion to act as a barrier to lock moisture in the skin.

Behenyl alcohol.

Behenyl alcohol is also called 1-Docosanol. This is a saturated fatty acid made up of 22 carbon atoms.

The molecule is used in cosmetics and flex-foam pads as an emollient; a moisturizer, emulsifier, and thickener.

The molecule has been approved by the Food and Drug Administration (FDA) to be used as an antiviral agent in cosmetics. It helps in reducing cold sores caused by the herpes simplex virus.

Pigment red 57.1

This is a calcium salt pigment that has high dispersibility and good resistance to heat. It has slow viscosity.

The chemical is used in flex-foam as a colorant to give the material a characteristic color.

Pigment Blue 15.

This is a material of copper phthalocyanine. It is a copper chelate that binds to the flex foam. It is used as a colorant.

Ditallowethyl hydroxyethylmonium methosulfate.

This substance is added to the flex foam pads as a surfactant to make layers that enhance the feel, breathability, absorbency; the ability of the material to repel fluid.


Fragrances are added to the flex foam pads to provide a light, clean scent. This prevents the pads from having period odors.

What is the structure of flex foam pads?

Flex foam pads are designed to improve efficiency while increasing the comfortability of the user.

The structure of the pad has the following parts:

  • Absorbent holes.
  • Grooves.
  • Core.
  • Top layer.
  • Wings.
  • Back sheet.

Absorbent holes.

The absorbent holes on the flex foam pads help in pulling the fluid into the core of the pad.


The grooves are added to the structure of flex foam pads to help them conform to the user’s body.


Flex foam pads contain a two-layered core made of proprietary polyacrylate foam material that helps in absorbing the period fluids.

Top layer. 

The top layer of flex foam is made up of soft, breathable, non-woven material that helps in keeping the person wearing the pad comfortable and dry.

It uses polypropylene and polyethylene plastic polymers to give the pad good structure and flexibility.


The wings contain adhesives such as hot melt adhesives. It helps to keep the pad in place and also protects the side of the wearer’s underwear.


This is a back protective layer that keeps period fluid from reaching the underwear. It contains adhesives such as melt adhesives that help the pad stay in place.

Is flex-foam toxic?

According to a product description article on the website, FlexFoam has been dermatologically tested and approved as skin-friendly by the Skin Health Alliance, an independent organization led by dermatologists and scientists. 


This article has answered the question of the biodegradability of flex foam.

It has also covered other areas such as the components of flex-foam and their purpose, the toxicity of flex foam, and the biodegradation process.

For any questions or comments please use the comment section below.

Frequently Asked Questions (FAQs): is flex-foam biodegradable?

Is period blood good for your face?

No, for now, there is no scientific backup for this practice. 

It is also worthy to note that some people may contain viral, bacterial, or fungal diseases in their reproductive tract and the microbes might come out with the period blood, applying the blood to the face may be spreading the microbes to the body.

Why should we not use cloth during periods?

Clothes do not have agents to absorb fluid and also they may be unclean, posing the danger of pathogens entering the urinary tract.

Why are pads toxic?

Although not all pads are toxic, some contain compounds such as phthalates which when one is exposed for long may cause infections in the urinary tract.


Always FlexFoam: Made Differently, Works Differently: Always Flex Foam To give you the confidence, comfort, and protection you deserve. Period.

The product description on

Retrieved from:

MacEachern, William; Jillson, Otis (1964). “A Practical Sunscreen – ‘Red Vet Pet'”. Archives of Dermatology. 89 (1): 147–50. doi:10.1001/archderm.1964.015902501530

J. A. Pomposo, J. Rodríguez and H. Grande “Polypyrrole-based conducting hot melt adhesives for EMI shielding applications” Synthetic Metals, Volume 104, Issue 2, 1999, Pages 107–111 doi:10.1016/S0379-

Leave a Comment