Polyvinylidene chloride is a clear as well as flexible artificial thermoplastic produced by the polymerization of vinylidene chloride. It is optically transparent with a high degree of gloss and has excellent moisture and oxygen barrier properties similar to metalized films. These films have a wide range of uses across various industrial areas including the food packaging industry, pharmaceutical industry, and many more.

The development of different products and goods gave rise to the need for proper packaging of the items in order to extend the products' shelf life. Packaging films have been developed considering several product requirements and facts. There are numerous options that prioritize tear strength and durability, good storage and safe distribution, food safety and its freshness, and safety from environmental factors such as light, gas, moisture, and temperature. Among many other packaging films available in the market, Polyvinylidene chloride (PVDC) coated films are one of the best types of packaging films.

What are PVDC Coated Films?

PVDC stands for polyvinylidene chloride. PVDC is a versatile and unique thermoplastic synthetic polymerized chloride made by polymerization. A polyvinylidene chloride coated film provides an excellent barrier to aroma, oxygen, and gas. These features make PVDC films an ideal option for the packaging of products like biscuits, cheese, wafers, drugs, and meat. These films are accessible in a see-through form, and hence, are suitable for transparent packaging. They are mostly used in the packaging of cosmetics, drugs, food, and other delicate or perishable products for their better shelf life. 

In comparison with various common films, PVDC coated films have better moisture and gas barrier properties, as well as better heat sealability. PVDC is highly resistant to several chemicals including oil and grease. Moreover, it can be easily laminated and extruded. It is also microwavable and printable using common ink systems. It is made by adding polymerization of 1,1-dichloroethene. The homopolymer is actually too hard to make as it decomposes below its melting temperature.

Is PVDC Biodegradable?

Polyvinylidene chloride is a form of plastic that causes pollution and leads to landfills. Biodegradable packaging films like PHBV (Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)) offer high mechanical performance throughout their life-time as original PVDC films and are totally bio-degradable after the end of life.

General Properties of PVDC

There are several types of PVDC coated films. One of the most common types of PVDC films is biaxial oriented PVDC film. It has low elasticity and offers low water absorption and excellent bond strength. Moreover, it also possesses good cling features and making it perfect for foodstuff wrap applications. Owing to the high chemical resistance, inertness, and low odor, PVDC is suitable for numerous packaging applications. Even though PVDC is recyclable, but most PVDC coated films are not recycled, because it is often utilized as an extremely thin coating that cannot be easily extracted. 

Vinylidene chloride is sometimes copolymerized with other monomers. A common copolymer contains around 15% vinyl chloride and 85% vinylidene chloride. This polymer film is recognized with the trade name SaranTM. Due to its higher cost, it is usually combined with other inexpensive plastics such as polyethylene, nylon, and polypropylene. It is typically applied as a laminate or thin coating or it is co-extruded with other resins to produce a double layer film or sheet to improve the blockade properties of the inexpensive base film.

The key properties of PVDC coated films are:

• Excellent Optics
• Excellent consistency
• Excellent barrier for oxygen, moisture, aroma, gases
• Good machinability
• Solvent Free coatings, 
• Better Printability
• Heat Sealable
• Low-Temperature seal, and high seal integrity coatings.

What is Triggering the Need for PVDC Coated Films?

Erosion is a destructive corrosion caused by electrochemical or chemical reactions between the surrounding environment and metals. It is a kind of destruction that quietly arises over time. In today’s life, healthy eating is the most important factor to stay fit and healthy. The foodstuff we eat should be safe and fresh and must be packed in coated films. Some films that are available in the market can cause corrosion. However, PVDC coated films can be a solution to this problem. These films are in huge demand due to their excellent resistance to water vapour and their ability to effectively act as a barrier for oxygen which keeps the food items hygienic and safe. 

What are the Different Applications of PVDC Coated films?

Packaging of a foodstuff is an important factor for the safety and better storage of products for a given period of time. Thus, to maintain the safety of the product PVDC coated films are in high demand in today’s life. PVDC coated films are utilized for the packaging of foodstuffs because they have low stretch and offer low water absorption and outstanding bond strength. Pharmaceutical packaging of blister is made of PVDC coated films providing good resistance to water vapour as well as it acts as an effective blockade for oxygen, owing to which their application is growing in blister packaging. India’s packaging industry is the 5th largest in the world. In 2019, according to the Plastics Industry Association of India, the Indian packaging industry is rising by 22 to 25 percent every year. 

PVDC coated films are mostly used in the food & beverage and acrylic coated films industry. Acrylic and PVDC coated films find a wide range of applications in the food & beverage industry for labelling, packaging, and other applications. Moreover, PVDC coated films offer high gas blockade and outstanding seal strength. These films possess high stiffness, outstanding oxygen & moisture barrier, good aroma barrier, low sealing threshold, and superior dimensional stability, which makes them appropriate for foodstuff packaging. 

PVDC plays an important role in blister packaging as coatings or laminations. They offer enhanced blockade to both water vapor and oxygen while many other barrier polymer provides just one or the other. Actually, PVDC products are copolymers of VDC (vinylidene chloride) and other comonomers. PVDC coating films have been utilized with duplex (PVDC/PVC) as well as triplex (PVDC/PE/PVC) structure being the most widely used. About, 67 percent of the blockade blister packaging industries use these PVDC coated films. 

How has COVID-19 Pandemic Impacted the Demand for PVDC Coated Films?

Recently, the outbreak of the COVID-19 disease pandemic led to a decline in manufacturing activities in the first six months of 2020 all across the world. It resulted in a reduced need for PVDC coated films from numerous end-user organizations. However, the COVID-19 disease pandemic has affected the demand for PVDC coated films on the positive side. Funding packages provided by governments of several countries will aid to continue the liquidity of PVDC coated films all over the globe.  

Is PVC Different from PVDC?

Polyvinyl Chloride (PVC) is a thermoplastic polymer usually made up of chloroethene monomers. This material might be a common polymer material, along with polypropylene and polyethene. The rigid PVC material is important in construction requirements, while the flexible PVC form is helpful for cables and wiring. The main advantage of PVC is its low cost and simple thermoforming, which is performed via chlorination. PVC has numerous notable properties such as poor heat stability, high electrical insulation, chemical resistance, high hardness & beneficial machinery properties, and good flame retardancy.

The Bottom Line

Several key players in many industries are collaborating and manufacturing PVDC coated films which include industries like Cosmo Films Ltd. (India), B.C. Jindal Group (India), SKC, Inc. (US), Vacmet India Ltd (India), and Vibac Group S.p.A. (Italy). These industries are involved in adopting several organic and inorganic strategies to develop more efficient PVDC films that can be used in a wide spectrum of industrial applications. To sum up, the development of more advanced PVDC coated films is underway and is soon going to be a success.