Sweetlittledollar
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Oct 7, 2023
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In the scorching summer days, flip flops are essential footwear for everyone. In the market, we often come across two common materials: PVC and EVA. So, which material is better for flip flops? This is a question worth discussing.
PVC and EVA are both a kind of plastic material, and the products they make are very common in our life, such as ladies slippers. In many cases, these two materials can also substitute for each other, so many people can’t tell the difference between them. Today, let’s briefly introduce what material EVA and PVC are, and which is better.
PVC (Polyvinyl Chloride) slippers are a type of footwear made from PVC material. PVC is a synthetic plastic polymer widely used for various applications. The advantages of PVC slippers lie in their durable material, resistance to wear, a wide range of colors, and the ability to meet diverse consumer needs. Additionally, the manufacturing cost of PVC slippers is relatively low, making them more budget friendly in terms of pricing.
However, PVC material is not breathable, which can make the feet feel hot and damp. Furthermore, PVC material is relatively rigid, making it susceptible to damage when subjected to impacts or friction.
Chemical Composition: PVC is a white powder with an amorphous structure. It is susceptible to degradation when exposed to prolonged sunlight or temperatures of around 100℃, leading to the release of hydrogen chloride and potential discoloration, which may adversely affect its mechanical properties.
Temperature Range: PVC has a service temperature range typically between 15 degrees and 55 degrees Celsius. It operates most effectively within this temperature range.
Stabilization Requirement: To enhance its stability, PVC often requires the addition of stabilizers when used in various applications.
EVA (Ethylene Vinyl Acetate) slippers are a type of footwear made from EVA foam, a elastomeric material known for its lightweight and cushioning properties. EVA is commonly used in the production of various types of footwear, including flip flops, sandals, and slippers.
They have good toughness and elasticity, along with a certain level of waterproof performance. The advantages of EVA slippers lie in their soft and comfortable material, as well as their excellent resistance to wear. Additionally, EVA slippers offer good breathability, effectively preventing the feet from feeling hot and damp.
However, the manufacturing cost of EVA slippers is relatively high, resulting in a higher price point. Moreover, EVA material has relatively lower durability and can deform or become damaged when exposed to high temperatures or strong chemical substances such as acids and bases.
Shock Absorption: EVA boasts resilience and exceptional tensile strength, making it an excellent material for shock absorption and cushioning.
Waterproof and Sound Insulation: Its closed cell structure ensures that it remains impervious to water, while also providing effective sound insulation.
Thermal Insulation: EVA’s bubble like structure imparts excellent thermal insulation properties.
Ease of Processing: EVA’s absence of fixed joints makes it easily processable through methods such as hot pressing, cutting, and fitting.
Corrosion Resistance: EVA is naturally antibacterial, non toxic, and odorless, making it resistant to acid and alkali corrosion.So, which material is better for slippers? Actually, there is no clear answer to this question. Because different consumers have different needs for slippers, and different materials also have their own advantages and disadvantages. For example, if you focus on durability and waterproof performance, you can choose PVC slippers; If you focus on comfort and breathability, you can choose EVA slippers.
EVA is 30% lighter than PVC — This gives the film a better yield and reduces shipping costs. EVA has excellent RF sealing properties — The same RF sealing equipment can be used with PVC and EVA, so there are no extra costs for re tooling.
The PVC Soles have great oil resistance, abrasion resistance, good insulation properties. Plastic sole is normally used by people working closely with water or places where there is rain. Disadvantages: non slip performance is poor, poor texture, poor ventilation.
Durability — EVA soles can last longer than other soles. This way, your EVA sneakers can keep up with you for as long as you need them to.
EVA stands for ethylene vinyl acetate, which is a soft and flexible plastic that’s also very strong. EVA is often used as a safe alternative to PVC. When combined with heat, pressure, and other plastics, EVA becomes closed cell EVA foam.
Both EVA and PVC slippers can develop unpleasant odors over time. EVA slippers, in particular, do not inherently have a smell when initially purchased. However, with prolonged use or exposure to higher temperatures, mold and bacteria can thrive on EVA slippers.When stored in cool or humid environments, these bacteria can multiply rapidly, generating various alcohols and lipids, which are the primary culprits behind the odor in EVA slippers. On the other hand, PVC slippers may emit odors due to a row of small openings located on or around the shoe’s sole. When soapy water or bathwater containing human dandruff, sebum, and other contaminants enter these openings, they can undergo fermentation, resulting in a foul smell over time. Additionally, if residual soapy water or shower gel from bathing is not thoroughly rinsed away, a similar odor may develop.
In addition, considering the specific usage requirements for different occasions, it is important to choose the appropriate material. For instance, in areas with high humidity like bathrooms and kitchens, it is advisable to opt for PVC slippers due to their superior slip resistance. Conversely, in drier environments such as bedrooms and living rooms, EVA slippers might be a better choice as they are softer, more comfortable, and environmentally friendly.
✔ Using high quality EVA material to make an ultra light sole;
✔ Suitable for many occasions, such as walking and the beach;
✔ Using injection process to make high quality flip flops;
✔ Embossed texture design of this sole improves grip ;
✔ Professional designer team design according to ergonomics;
✔ A variety of colors for your choice or custom colors.
It's (literally) clear that the PVC shoe is the new must have item for your shoe closet. They are everywhere – from high street fashion houses to the more affordable shoe stores. Whether it's a combination of plastic upper and heel, or with cut in portions of leather in the upper, it's pretty hard not to like something about these shoes. We recently read an article from Vogue (May 2018) where they claimed that PVC shoes were actually bad for your feet and overall health. But are they really? This week Elouise breaks down this season's essential foot accessory.
OK, there is something striking a cord with my inner child when I look at these shoes. Memories of dressing up in my princess costume which included a pair of high heel pink plastic mules have come flooding back to me. I remember thinking how grown up I looked. Not only were the shoes high heels, a big no no on children according to my Mum (and rightfully so too), but they were pink and had a pale pink transparent plastic heel. I loved them so much, looked at them for hours and walked around the house proudly and with purpose! I think this may be where my love affair with shoes actually started. I had my first experience of gripping pain and devastation with these shoes when I snapped the heel off them while walking down the driveway. Cried for hours! Who knew plastic shoes could cause so much emotion? While this certainly seems the case with little girls… this big girl still loves them!
But are they really bad for us? Vogue seems to think so… And here's why!
Risk of fungal and bacterial infection
I have to admit this picture does give me the heebie jeebies. We are professionals first and foremost, but both Ele and I have hyperhidrosis or excess sweating on the bottom of our list of preferred things to treat! And this picture does not look healthy. There are around 30,000 sweat glands in the foot and it you enclose them in a plastic boot condensation will form. Bacteria and fungus love warm moist environments and thrive in this condition. Bacterial infections generally are very smelly and fungal infections are really troublesome to get rid of. Not to mention it would be like a Slip N Slide in there! Y U C K. And as we know friction also causes pain! Additionally, if there is a high heel on the boot there would also be more movement on and around the metatarsal heads increasing the risk of metatarsalgia.
TWH Solution: Don't wear enclosed boots! We advise that you choose a style that has an open toe and avoid above ankle boots, to allow air to circulate in and around the foot and leg. Maybe don your best pair of fishnet socks in combination with your PVC safety boots. This will absorb some of the sweat. And do not wear them on the hottest day in Summer!
2. PVC shoes are rigid and lack flexibility to accommodate swelling
According to Dr. Rock Positano, director of the Non-surgical Foot and Ankle Service at Hospital for Special Surgery in New York, PVC shoes are really rigid and inflexible. Are they? That’s news to me! I’m not sure Dr Rock has tried on too many of these shoes in his time… although I shouldn’t make assumptions (we don't know what his interests are outside of work). No judgement from here Dr Rock but I’m not sure I agree with you on this one, as often the PVC plastic used in these heels has quite a bit of give (well the ones I've worn and tried anyway).
Dr Rock goes on to say that the foot can expand up to to 2 sizes and the PVC shoe won't expand like leather does to accommodate this. First of all, unless you have severe venous insufficiency, a problem with your lymph system or some other systemic condition, it’s a stretch to say that the foot increases 2 sizes throughout the day. Also, I don't know any leather shoe that wouldn't hurt if the foot increases 2 whole sizes. Even kangaroo skin which is incidentally the softest and strongest of leathers would struggle to accommodate this much oedema. Dr Rock does make a very valid point though about the PVC shoe – He states that if the sole of the shoe is PVC then it will lack shock absorption and flexibility which can cause pain to the foot. This we agree on!
This lucite soled shoe is an example of what to try to avoid.
TWH Solution: Shop at the end of the day! The foot is generally at its biggest at the end of the day which will allow you to get the correct size. Choose a style that allows for some increase in size and try to choose a shoe that has a leather or rubber sole that will allow for more shock absorption and overall comfort.
3. PVC shoes cause blisters
Vogue’s Fashion News Editor Chioma Nnadi recalls the severe blisters that formed on her feet when she walked for hours around the streets of New York in the height of Summer in PVC shoes. Depending on the shape of the upper and where the edge of the upper ends on the foot, there could be an increased risk of blistering on the foot. Sure this is true, but leather straps can also cause severe blistering if they are poorly placed or there is stiff stitching over a flexion point of the foot. I think the point here is the combination of hot weather, extended periods of walking and poor upper shape are all conducive to increasing the risk of blistering.
TWH Solution: Be sensible with the choice of PVC shoe with regards to heel height, shape and placement of straps and if there is any stitching in the upper. If the shoe upper finishes away from obvious flexion points(where a joint bends) the risk of blistering should be reduced. I would like to mention that a PVC upper will actually accommodate minor toe deformities quite well as it is reasonably forgiving! Also don’t wear these shoes for hours on end in Summer! The heat will cause increased sweating which will increase movement and friction and therefore blistering.
I tried on these Tony Bianco mules the other day and they were really comfortable. The midi heel was the perfect height for a comfortable forefoot and the PVC upper felt supportive but certainly not tight. They came in a range of really pretty colours too. These are fashion shoes though people! We are not suggesting that you walk for hours on end in these, but they are a perfect choice for dinner or a cocktail party. We have these Tony Bianco’s up on TWH’s Shoe equation and a selection of this season’s PVC shoes for your perusal.
What do you think? We would love to hear your thoughts on this shoe trend.
“What is the difference between TEP and EVA? What does tunit promise me? Is PVC glue? What is the sole of these shoes made of? ”- the modern buyer wants to know everything. In order not to smash his face in front of him and be able to explain whether such a sole suits him in soles, carefully read this article. In it, process engineer Igor Okorokov tells what materials the soles of shoes are made of and what makes each of them so good.
Igor Okorokov - engineer-technologist of shoe production, graduate of Vitebsk State Technological University of Light Industry. Since 2002, he has been working as a specialist in various shoe companies in Russia.
- engineer-technologist of shoe production, graduate of Vitebsk State Technological University of Light Industry. Since 2002, he has been working as a specialist in various shoe companies in Russia.
Materials used for the manufacture of soles
The sole is one of the most important parts of the shoe, which protects it from wear and largely determines its service life. It is the sole that is subjected to intense mechanical stress, abrasion on the ground and repeated deformations. Therefore, the materials used for the manufacture of soles should be as resistant to environmental influences as possible. In this article I will tell you what materials the sole can be made of and what are the advantages and disadvantages of each of them.
Outsole Mounting Methods
There are two main methods for attaching soles: glue and injection. But contrary to popular belief, the fastening technology does not affect the consumer properties of shoes. The glue method is used for classic and model weekend shoes, most often on leather or tunne soles. In the manufacture of comfortable shoes for everyday wear, the injection method is most often used.
Soles made of different materials are characterized by different methods of fastening. Soles made of polyurethane are most often made by direct casting, but in rare cases, the pre-molded sole is glued to the top. Soles from TPU are obtained by injection molding at high temperature under pressure. Also made of thermopolyurethane heels. The bottom of thermoplastic elastomer is molded by injection molding, and then glued. PVC soles are most often fixed by injection molding in the manufacture of shoes for outdoor activities and everyday wear. EVA soles are attached to the top of the shoe only by injection molding, and tunit and leather soles are only glued. For TPR, both options can be applied.
Soles made of polyurethane (PU, PU)
Advantages: Polyurethane has good operational properties: it weighs little, since it has a porous structure, is well resistant to abrasion, flexible, has excellent shock absorption and good thermal insulation. The soles made of polyurethane are light and flexible, therefore they are used in shoes where these characteristics are of particular importance.
Disadvantages: The porous structure of polyurethane is also a kind of flip side of the coin. For example, because of it, the polyurethane sole has poor adhesion to snow and ice, so winter shoes with PU soles slip very much. Also a minus is the high density of the material and loss of elasticity at low (from -20 degrees) temperatures. The consequence of this is faults in the places of the bend of the sole, the rate of occurrence of which depends on the characteristics of the operation of the shoe, in particular, on the person’s gait, degree of mobility and other factors.
Polyurethane Soles (TPU, TPU)
Advantages: Polyurethane has a fairly high density, so that it is possible to make soles with a deep tread from it, which provide excellent traction. Also, the advantages of TPU are high wear resistance and resistance to deformation, including cuts and punctures.
Disadvantages: The high density of polyurethane is at the same time its drawback, because because of this the weight of the thermo-polyurethane sole is quite large, and the elasticity and thermal insulation leave much to be desired. To improve these characteristics, TPUs are often combined with polyurethane, thereby achieving a reduction in the weight of the sole, increasing its thermal insulation and elasticity. This method is called two-composition molding, and it is quite simple to find out: the sole made using this technology consists of two layers, and the upper layer is made of polyurethane (PU), and the lower one in contact with the ground is made of polyurethane.
Thermoplastic soles (TEP, TRP)
Advantages: This material can be considered year-round. It is durable, flexible, resistant to frost and wear. TEP provides good cushioning and traction. Thanks to the manufacturing technology of soles from TEC, its outer layer is monolithic, which provides strength and the internal volume is porous, retaining heat. Thermoelastoplast can be recycled, which means that its use in the soles saves resources and does not pollute the environment.
Disadvantages: At high and very low temperatures (above 50 degrees and below -45 degrees) TEP loses its properties, so it is used only in everyday shoes and, by the way, is rarely used for special shoes.
Soles made of polyvinyl chloride (PVC)
Advantages: PVC soles resist abrasion, are resistant to aggressive environments and are easy to manufacture. They are often used in home and children's shoes, and earlier they were especially widely used for special shoes, since when mixed with rubber, PVC receives properties such as oil and gas resistance.
Disadvantages: PVC is used only in the manufacture of casual shoes for autumn or spring, because this material has a large mass and low frost resistance, not withstanding temperatures below -20 degrees. In addition, the PVC sole does not attach well to the leather upper of the shoe, so quality leather shoes with a PVC sole are complex and expensive to manufacture.
Ethylene vinyl acetate soles (EVA)
Advantages: EVA is a very lightweight material with good cushioning properties. It is used mainly in children's, home, summer and beach shoes, and in sports shoes - in the form of inserts, because it is able to absorb and distribute shock loads.
Disadvantages: Over time, EVA soles lose their cushioning properties. This is due to the fact that the pore walls are destroyed, and the entire mass of EVA becomes flatter and less elastic. Also, EVA is not suitable as a material for winter shoes, since this material is very slippery and unstable to frost.
Thermoplastic rubber soles (TPR, TPR)
Thermoplastic rubber - This is shoe rubber made from synthetic rubber, which is stronger than natural rubber, but no less elastic. However, modern technology allows using various additives to increase its flexibility.
Advantages: Thermoplastic rubber has a low density and, accordingly, a lower mass than other materials. There are no through pores in it, so moisture does not pass through it. However, there are surface pores in the TPR, and they provide high thermal protection. In addition, TPR, like other porous rubbers, is an elastic material that provides good cushioning properties. Thanks to this characteristic, shoes with soles made of TPD relieve unnecessary stress on the legs and spine.
Disadvantages: The low density of the material can be not only a virtue, but also a disadvantage. In the case of TPR, it leads to the fact that the sole of this material does not differ in particularly outstanding heat-shielding properties. In addition, in wet and frosty weather, the thermoplastic rubber sole slides heavily.
Soles made of leather (leather)
Advantages: Leather sole is used in all types of shoes, including children's, home and model all seasons. Leather-soled shoes look great and allow the foot to breathe, as it is a natural membrane.
Disadvantages: When worn in wet weather, the leather sole may be deformed, and care of it implies the constant use of special sprays and impregnations. The leather has low wear resistance, so the installation of prophylaxis is recommended on leather soles, and for winter shoes it is mandatory, otherwise without it the sole will slide on ice and snow and deform even faster.
Tunit soles (tunit)
Tunit - This is a rubber with the inclusion of leather fibers, so the second name of this material is “leather jacket”.
Advantages: In appearance, hardness and ductility, tunitic soles are similar to leather ones, but they behave better in operation: they almost do not wear out and do not get wet. It is easy to apply relief to such soles, which gives them a slightly greater grip on the surface than the leather.
Disadvantages: But even so, shoes with tunit soles are very slippery due to the high stiffness of the material. Therefore, tunit is used in the manufacture of only summer and spring-autumn shoes with the adhesive method of fastening.
Soles made of wood (wood)
Advantages: Wood is an environmentally friendly and very hygienic material, and wooden soles have an original appearance. However, recently instead of wood, glued plywood has been used more often for making shoes. It can be made of birch, oak, beech or linden wood, and as a material it is easier to machine, is well formed and inexpensively. Soles using cork material are also popular. When dealing with them, you need to understand that cork, because of its natural softness, cannot serve as the main material for making soles, so cork is used only for decorative covering.
Disadvantages: Wooden soles are tough, wear out quickly and have poor water resistance. In the manufacture of such soles, a lot of material is consumed. Tight cork is prone to steps and defects due to the softness of the material.
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PVC – a major source of phthalates
PVC – a major source of phthalates
Polyvinyl chloride, or PVC, is a major source of phthalates – which are the same dangerous plastic softeners banned from children's toys last year.
2008 law banning phthalates from children's toys does not cover the PVC in school supplies
The 2008 law banning phthalates from children's toys does not cover the PVC in school supplies, with which our children come in contact on a daily basis.
Phthalates harm children's health and development by interfering with natural hormone functioning and have been linked to birth defects in baby boys, testicular cancer, liver problems, and early onset of puberty in girls – which is a risk factor for later-life breast cancer.
Why worry about PVC-free school supplies?
Many children's school supplies, such as lunchboxes, backpacks and binders, can be made out of PVC-a toxic plastic that is dangerous to our health and the environment.
PVC contains dangerous chemical additives including phthalates, lead, cadmium, and/or organotins, which can be toxic to your child's health. These toxic additives can leach out or evaporate into the air over time, posing unnecessary dangers to children.
Here are some school supply shopping tips you can start using today:
The "2009 Back to School Guide to PVC-Free School Supplies" to help you avoid dangerous PVC products when back-to-school shopping.
To download the complete guide,
To download a pocket-size guide to carry with you when you shop,
Below are some examples of school supplies which are OK and which to avoid.
The Center for Health, Environment, and Justice (CHEJ) - through its ongoing campaign "PVC: The Poison Plastic - The Campaign for Safe, Healthy Consumer Products" -- has posted itsto help you avoid dangerous PVC products when back-to-school shopping.To download the complete guide, click here To download a pocket-size guide to carry with you when you shop, click here Below are some examples of school supplies which are OK and which to avoid.
Pictures of OK products
Pictures of PVC products to AVOID
PVC Labeling
PVC products are often labeled with the words "vinyl" on the packaging, such as vinyl 3-ring binders.
PVC can also be identified by looking for the number "3" inside, or the letters "V" or "PVC" underneath, the universal recycling symbol. Just remember, bad news comes in #3's, so don't buy PVC! Make sure the binders have metal rings. These colorful binders are leather with metal rings.
Backpacks
Avoid backpacks with shiny plastic designs as they often contain PVC and may contain lead. Fabric backpacks can have cloth appliqués to make them attractive and safe.
Art Supplies
Modeling clays are often loaded with phthalates. Look for clays made without PVC and phthalates like Crayola Air-Dry clay.
Notebooks
Avoid notebooks containing metal spirals encased in colored plastic. The colored plastic coating on the metal spirals usually contains PVC. Select notebooks with uncovered metal spirals to avoid PVC.
Paper Clips
Most colored paper clips are coated with PVC. Stick to the plain metal paperclips, unless you can see that they are clearly made of colored metal.
Shoes
Shoes similar to (or “knockoffs”) Crocs, like the Kamik Doodle, are made with PVC. Many of the charms for Crocs are also made with PVC.
Crocs are PVC free; and all Nike, Puma, and L.L. Bean shoes are PVC free. (clockwise from top: Crocs, Nike, Puma, L.L.Bean)
Unfortunately, items made from shiny plastics and vinyl have PVCs in them most of the time, so just check before you buy!
AVOID THESE ►
Clear bag Shiny handbag Cosmetics bag
PVC flashdrive Plastic lunchbag Vinyl tape
PVC pencilcases PVC chair Plastic raincoat
Vinyl CD sleeve Vinyl magazine holder Banned PVC toys