DMDM Hydantoin: what need to know?

What is DMDM Hydantoin?

DMDM Hydantoin, the full name is 1,3 hydroxymethyl-5,5 dimethyl hydantoin. Chemical name: 1,3-Dimethyloldimethylhydantoin, DMDMH for short. Molecular weight C7H12N2O4, colorless and transparent liquid, slightly aldehyde smell, freezing point -11 ℃ is formaldehyde emission , DMDM Hydantoin is often used as preservative, fungicide, can inhibit the growth of fungi, yeast, bacteria, this component will decompose to produce formaldehyde , may be irritating to the skin and have a certain risk of allergy.

Does DMDM Hydantoin have any health effects?

DMDM Hydantoin is an ingredient of mild concern, suspected of causing skin or immune system toxicity, based on a synthesis of research literature from China, Canada, the United States, Japan, and the European Union.

How to produce  DMDM hydantoin?

Wide variety of DMDM Hydantoin derivatives， There are many kinds of DMDM Hydantoin derivatives with different structures. The source mainly depends on chemical synthesis, and the corresponding synthesis methods are also different. Since the hydantoin derivatives isolated from white aconite are all substituted at the 5-position. Therefore, the synthesis of 5-position substituted hydantoin derivatives will be briefly described below.

1. Bucherer-Bergs synthesis

The Bucherer-Bergs synthesis method is currently the most widely used synthesis method for hydantoin derivatives. This method was proposed by Bucherer as early as the 1950s, and researchers have continued to improve it for decades. In most cases, in 50% ethanol solution, aldehyde or ketone and sodium cyanide (or potassium cyanide) and ammonium carbonate directly generate hydantoin at 60-70°C. The general reaction formula is as follows:

The method is cheap and easy to obtain raw materials, relatively simple in operation, good in product yield and high in purity, and both the solvent and the mother liquor can be recycled and reused, which is easy to realize industrialization and is an economical and feasible synthesis method. However, this method uses highly toxic cyanide, so it is necessary to increase the waste liquid post-processing device, and the pressure on environmental protection is relatively large. In addition, this method is carried out under alkaline conditions. For compounds such as aldehydes and phenols that are easily oxidized, oxidation by-products are easily generated, and separation is difficult, which has a great impact on the purity and quality of products.

2. Allantoin method

The chemical name of allantoin is 5-ureidohydantoin, which is one of the few natural hydantoin derivatives. It is the product of purine metabolism and exists in the urine of most mammals and embryos of animals. , originally obtained from bovine sacs, and now it has been synthesized in large quantities from simple compounds in industry. Allantoin undergoes proton dissociation under strong acid conditions to generate positive hydantoin ions, which then undergo electrophilic reaction with highly activated aromatic rings such as phenol and aromatic ethers to generate hydantoin derivatives. The general reaction formula is as follows:

The method is simple to operate, does not use highly toxic cyanide, has little pressure on environmental protection, and is convenient for post-processing, and is a clean and feasible synthesis method. However, compared with the Bucherer-Bergs synthesis method, this method has a lower yield, and can only be used for the synthesis of highly activated aromatic ring-substituted hydantoin derivatives. The application scope is relatively narrow, which limits its large-scale use.

3. Acid ring closure method

DMDM Hydantoin derivatives are obtained by reacting amino acid derivatives with cyano-substituted compounds such as cyanate esters and cyanamides. The general reaction formula is as follows:

Although this method can synthesize 1,3-substituted hydantoin, the yield is generally satisfactory, but amino acids are often obtained by hydrolysis of hydantoin, and N-substituted amino acids generally cannot be obtained from natural amino acids, and the source is more Rare, the price is often more expensive than the target product. In addition, a strong acid catalytic medium is used in the synthesis, and the highly toxic cyanate and cyanamide are easy to generate volatile cyanic acid under these conditions, which is more dangerous to the operator than the Bucherer-Bergs synthesis method. The separation steps and The post-processing of the waste liquid is also more complicated.

What are the properties of DMDM hydantoin?

The chemistry of DMDM Hydantoin is a broad-spectrum and efficient antibacterial preservative, which maintains stable antibacterial properties in water phase and oil-water emulsion, and has good compatibility with various emulsifiers and surfactants.

Soluble in water and ethanol, heat resistant. Store in a cool and dry environment, it is strictly forbidden to mix with toxic and harmful substances to avoid pollution. The shelf life is two years. The antibacterial properties of water-phase emulsion and oil-water emulsion are stable . DMDM Hydantoin is a broad-spectrum, high-efficiency antibacterial preservative, which can be compatible with various emulsifiers and surfactants against Gram-positive bacteria, Gram-negative bacteria, molds, yeasts, etc. Always stable using a wide pH and temperature range. It is a low-toxic product, and the LD50 of rat red mouth is 3000MG/KG.

What are the applications of DMDM hydantoin in cosmetics?

DMDM Hydantoin is mainly used to add to shampoos or conditioners, it can also be used as a preservative in cosmetics, and it can also be used in combination with iodopropynyl butylcarbamate. DMDM Hydantoin is suitable for all kinds of cosmetics and personal care, and can be used in daily chemical products such as shampoos, conditioners, shaving products, foundations, washes, lotions, creams, baby products, sunscreen products, cleansers, etc. Antiseptic sterilization (products that need to be washed). Leave-in and rinse-off products such as creams, lotions, shampoos, conditioners, gels and wipes. The general addition amount is 0.1 to 0.6%, which can be added at room temperature or up to 80°C. It has better synergistic anti-corrosion effect when used in conjunction with parabens, IPBC, Kaison, etc.

What are the applications of DMDM hydantoin in medicine?

DMDM Hydantoin can usually be used to make hydantoin derivatives, and can also be used in organic synthesis, chemical industry, medicine, textile and other fields; hydantoin can also kill viruses or fungi , thereby interfering with the normal metabolism of bacteria , it will also be widely used in the medical field; at present, hydantoin and its compounds can be biologically extracted from the traditional Chinese medicine unicornis, toad oil, certain marine organisms and fungi, and can also be used according to the structural formula. method for artificial synthesis. Hydantoin compounds have various pharmacological effects due to the different substitution sites and substituent groups of hydantoins, and the substituted groups have different biological activities. Hydantoin compounds have a wide range of pharmacological effects, involving the neuromuscular system, respiratory system, cardiovascular system, immune system, endocrine and other systems. In the treatment of inflammation, rheumatoid arthritis and other autoimmune systemic diseases, chronic obstructive pulmonary disease, diabetes, hypertension, tumors, convulsions, epilepsy and other diseases, hydantoin compounds have Good application prospect and research value. At present, most of the pharmacological effects of hydantoin compounds are still in the research stage, except that halogenated hydantoin compounds are widely used in disinfection and sterilization and phenylhydantoin compounds are used for anticonvulsant and arrhythmia.

Is DMDM hydantoin harmful to the skin?

At present, no obvious harm of DMDM Hydantoin to the skin has been found, and it is uncertain whether it will cause degeneration and reproductive toxicity. In daily life, normal exposure to hydantoin is not harmful to the skin. a certain stimulus. One of the most common is skin allergies. As a skin care additive, DMDMH is not harmful as long as the content does not exceed the standard, and DMDM hydantoin has a good effect on skin care and product stability.

Only for people allergic to formaldehyde, the presence of DMDMH may increase their allergy risk. If the additive dosage can be strictly controlled, the maximum concentration is 0.6%, which is within the concentration range required by the national standard . Damage to the skin.

How compatible is DMDM hydantoin in cosmetics?

DMDMH can be compatible with various components in cosmetics, and the test results show that its antibacterial ability is not affected by additives such as surfactants, proteins and emulsifiers in cosmetics.