Gel Padding
Friday, February 19th, 2010
Photo shows cut foam
polyurethane foam continuous line of foam cutting machine for the mattress, sofa, uphostry
What is polyurethane foam (polyurethane foam)?
(Smooth or semi-rigid polyurethane foam)
(1) polyurethane
Commonly abbreviated PU is a polymer consisting of a chain of organic units joined by urethane links. Polyurethane polymers are formed by reaction of a monomer containing at least two isocyanate functional groups with another monomer containing at least two alcohol groups in the presence of a catalyst. Polyurethane formulations cover an extremely wide range stiffness, hardness and density. These materials include low density flexible foam used in upholstery and bedding, low density rigid foam used for thermal insulation, soft solid elastomers used for gel pads and rollers for printing, and hard solid plastics used as a tool Electronic bezels and structural parts. Polyurethanes are widely used in flexible foam seat high-strength panels of rigid foam insulation, seals and microcellular foam gaskets, durable elastomeric wheels and tires, electrical potting compounds from, adhesives and sealants, high-performance, spandex fibers, seals, gaskets, carpet underlay, and hard plastic parts. Polyurethane products are often called "urethanes". Not to be confused with the substance urethane Specifically, also known as ethyl carbamate. Polyurethanes are produced from ethyl carbamate, nor do they contain.
The upholstery is the job of providing of furniture, especially seats with padding, springs, webbing and fabric or leather covers. The word "upholstery" comes from the Middle English words and Holden, ie to hold. The term applies to domestic furniture and also to applications in automobiles and boats. A person who works with upholstery is called an upholsterer, an apprentice upholsterer is sometimes called strange or trimmer.
Polyurethane products have many uses. More than three quarters of world consumption product in the form of polyurethane foams, with flexible and rigid types, be roughly equal in market size. In both cases, the foam is usually behind of other materials: flexible foams are behind upholstery fabrics in commercial and domestic furniture, rigid foams are inside the metal and plastic walls of most refrigerators and freezers, or behind paper, metals and other materials from the surface in the case of thermal insulation panels in the industry construction. Its use in garments is growing: for example, lining of the cups of brassieres. Polyurethane is also used for moldings which include door frames, columns, balustrades, window headers, pediments, medallions and rosettes.
The precursors of expanding polyurethane foam are available in many forms, for use in insulation, acoustic insulation, flotation, industrial coatings, packaging materials, and even cast instead of stuffing Upholstery. From that adhere to most surfaces and automatically fill the voids, have become very popular in these applications.
Chemistry
Polyurethanes are in the class of compounds called reactive polymers such as epoxies, unsaturated polyesters, and phenolic compounds. A urethane linkage is produced by reacting an isocyanate group,-N = C = O with a hydroxyl (alcohol) group,-OH. Polyurethanes are produced by the reaction of a polyisocyanate polyaddition with polyalcohol (polyol) in the presence of a catalyst and other additives. In this case, a polyisocyanate is a molecule with two or more isocyanate functional groups, R-(N = C = O) n ≥ 2 and a polyol is a molecule with two or more functional hydroxyl groups, R'-(OH) n ≥ 2. The reaction product is a polymer which contains the urethane-RNHCOOR '-. Isocyanates react with any molecule that contains an active hydrogen. Importantly, isocyanates react with water to form a bond of urea and carbon dioxide gas, but also react to form polyureas polyetheramines. Commercially, polyurethanes are produced by the reaction a liquid isocyanate with a liquid mixture of polyol, catalyst and additives. These two components are referred to as a polyurethane, or simply a system. The isocyanate is commonly known in North America as the 'A-side "or simply the" ISO ". The mixture of polyols and other additives commonly known as the "side B" or as "cop". This mixture can also be called a "resin" or "resin mixture. In Europe, meanings of "Side A-" and "side B" are reversed. Mixed resin additives may include chain extenders, links de la Cruz, surfactants, flame retardants fire, blowing agents, pigments and fillers.
The first essential component of a polyurethane polymer is the isocyanate. Molecules containing two isocyanate groups are called diisocyanates. These molecules also known as monomers or monomer units, since they themselves are used to produce polymers containing isocyanates three or more isocyanate functional groups. Can be classified as aromatic isocyanates such as diphenylmethane diisocyanate (MDI) or toluene diisocyanate (TDI) or aliphatic as hexamethylene diisocyanate (HDI) or isophorone diisocyanate (IPDI). An example of a polymeric isocyanate is polymeric diphenylmethane diisocyanate, a mixture molecules with two, three, four or more isocyanate groups, with an average of 2.7 functionality. Isocyanates can be modified in part the reaction of a polyol to form one prepolymer. A quasi-prepolymer is formed when the stoichiometric ratio of isocyanate to hydroxyl groups is greater than 2:1. A real prepolymer is formed when the stoichiometric ratio equals 2:1. The important features of isocyanates are their molecular backbone, NCO% content, functionality, and the viscosity.
The second essential component of a polyurethane polymer is the polyol. Molecules that contain two hydroxyl groups are called diols, the three hydroxyl groups triols were called, and so on. In practice, polyols are distinguished from short chain and low molecular weight chain extender glycol and assemblers such as horizontal ethylene glycol (EG), 1,4-butanediol (BDO), diethylene glycol (DEG), glycerine, and trimethylol propane (TMP). Polyols are polymers in their own right. They are formed by free-radical addition of propylene oxide (PO), ethylene oxide (EO) in a hydroxyl or amine containing initiator, or polyesterification of a di-acid as adipic acid, with glycols such as ethylene glycol or dipropylene glycol (DPG). Polyols extended with PO or equal opportunities are polyether polyols. Polyols formed by polyesterification are polyester polyols. The choice of initiator, extender, and the molecular weight of polyol greatly affect its physical state and properties physical characteristics of urethane polymers. Important characteristics of polyols are their molecular backbone, initiator, molecular weight,% primary hydroxyl groups, functionality, and viscosity.
PU reaction mechanism catalyzed by a tertiary carbon dioxide gas formed by reaction of amines in water and isocyanate
The polymerization reaction is catalyzed tertiary amines as dimethylcyclohexylamine, and organometallic salts such as dibutyltindilaurate. In addition, catalysts can be chosen according to whether they favor the urethane (gel) reaction, such as diazobicyclooctane, or urea (blow) reaction, such as bis-dimethylaminoethylether or, specifically, that the isocyanate trimerization reaction, as Octoate potassium.
One of the most desirable attributes of polyurethanes is their ability to become foam. Blowing agents, such as water, such as certain halocarbons HFC-245fa (1,1,1,3,3-pentafluoropropane) and HFC-134a (1,1,1,2-tetrafluoroethane), and hydrocarbons such as n-pentane, can be incorporated into the side of poly or added as an auxiliary flow. The isocyanate reacts with water to create carbon dioxide gas, which fills and expands cells created during the mixing process. The reaction is a three-step process. A water molecule reacts with an isocyanate group to form an acid dioxide. Carbamic acids are unstable and decompose to form carbon dioxide and an amine. The amine reacts with more isocyanate to give a substituted urea. The Water has a very low molecular weight, so although the weight percent of water may be small, the molar ratio of water can be high and significant amounts of urea produced. Urea is very soluble in the reaction mixture and tends to form separate "hard segment phase, which consists mainly of polyurea. The concentration and polyurea organization of these phases can have a significant impact on the properties of the polyurethane foam. [11] Halocarbons and hydrocarbons are chosen such that they boiling points at or near room temperature. Since the polymerization reaction is exothermic blowing agents volatilize into a gas during the reaction process. They fill and expand the cellular polymer matrix, creating a foam. It is important to know that the gas expansion does not create foam cells. Rather, form during the mixing process as nucleation sites for expansion as the gas fills and expands. In fact, high-density foam microcellular can be formed without the mechanically addition of blowing agents for foaming nucleation of poly mix before use.
(2) Use of polyurethane
1. Furniture
2. Car Seats
3. Varnish
4. Computer mouse pads
5. Glue
6. Wheels
7. Houses, sculptures and decorations
8. Boats
9. Construction sealants and fire stopping
10. Tennis Grips
11. Electronic Components
12. Binding of the industry
13. Wrap band Watch
1.Furniture
Polyurethane is also used in furniture manufacture for casting soft edges around table and the panel that are stylish, durable and prevent injury. These are used in school tables, hospital furniture and bank and shop counters and exhibitions.
Much of the foam used in chairs, sofas, mattresses and sacks Comfy is polyurethane foam. This type of foam is made by mixing polyols, isocyanates, catalysts, foaming agents and other additives and allowing the resulting foam to move freely. This can be done in a batch process, where relatively small blocks of foam made in an open ceiling of the mold, or continuously, where components are poured onto a conveyor belt inclined. The foam is cut to the shape and size for use in the manufacture of furniture.
Safety concerns about the flammability of polyurethane foam, especially in upholstered furniture, sometimes requires addition of this flame retardant foam.
Polyurethane is in other countries like the Netherlands used as a minimum solution for homes, offices, museums.
2. Car Seats
Flexible and semi-flexible polyurethane foams are widely used for automotive interior components and seats, headrests, armrests, roof liners and instrument panels,
Polyurethane foam in the bottom half of the mold in which it was made. Once mounted on a seat Car, makes this foam to the back seat. The forward-facing rear seat is part of the surface of the foam in the mold upside down. The two holes in the foam at the top of the image are for the posts of head.
Foam after removal of the mold.
Polyurethanes are used to make car seats in a remarkable way. The seat manufacturer has a mold for each seat model. The mold can be closed is a "shell" type of structure that allows rapid melting the seat cushion, called flexible molded foam, which is then upholstered after removal of the mold.
You can combine these two steps, called in-situ, foam-in-cloth or direct molding. In this case, the inner surface of the mold with hundreds of small holes that are connected to a vacuum in the collector. This creates a constant flow of air from the center of the mold of variety. The operator places the first assembly a complete, fully assembled Seat Cover in the mold and is adjusted so that the vacuum in the collector pulls the seat cover snugly into the mold surface. In some operations, this effect is enhanced by the addition of a thin film flexible plastic as a support structure to help the vacuum work more effectively. When the seat cover is in place, the operator places the metal frame seat in the mold and mold is closed. At this point the mold contains what could be viewed as an "empty chair", a web of security held in position correct by the vacuum in the collector and containing a hollow space with the metal structure in place.
The next step is to inject the chemical mixture polyurethane in the mold cavity. It is a mixture of two parts to be measured accurately through a mixing head. Then the mold is maintained at the reaction temperature preset until the foam chemical mixture has filled the mold, and formed stable soft foam. The time required is two to three minutes, depending on the size of the seat and the precise formulation and operating conditions. Then the mold is usually opened slightly for a minute or two for an additional curing time before the seat fully upholstered was deleted. The operator seat trim a fabric cover over the seat and placed over a conveyor belt.
3 Varnish
Polyurethane materials are commonly formulated as paints and varnishes for finishing topcoats or seal wood. This leads to use in a tough, abrasion resistant and durable coating that is popular for wood floors, but some find it difficult or unsuitable for finishing furniture, and other detailed parts. In connection with oil polyurethane varnish, lacquer or varnish forms a harder film which tends to de-laminate if subjected to heat or shock, fracturing the film and leaving white patches. This tendency increases when applied on soft woods like pine. This is also partly due to lower penetration of polyurethane on the wood. Various priming techniques are used to overcome this problem, including the use of certain oil varnishes, specified "dewaxed" shellac, clear penetrating epoxy, or oil modified "polyurethane designed for this purpose. polyurethane varnish may also lack the" hand-rubbed "brightness of drying oils, such as linseed or tung oil, in contrast, however, is capable of much faster and higher "build" of film making in two layers which may require several applications of oil. Polyurethane can also be applied on a straight oil finish, but by the relatively slow curing time oils, the presence of volatile byproducts of curing, and the need for oil prolonged exposure to oxygen, care must be taken that the oils are what sufficiently cured to accept the polyurethane.
Unlike drying oils and alkyds which cure, after evaporation of the solvent reaction with oxygen from the air, polyurethane coatings cure after evaporation of the solvent by a variety of chemical reactions within original mixture, or reacting with moisture in the air. Some products are "hybrids" and combine different aspects of their parent components. "The Oil-modified "polyurethanes, either waterborne or solvent, are currently finishing the most commonly used wood flooring.
Exterior use polyurethane varnish may be problematic because of its susceptibility to deterioration from exposure to ultra-violet light. It should be noted, however, that all transparent varnishes or translucent, and indeed all film-polymer coatings (iepaint, stain, epoxy, synthetic plastic, etc.) are susceptible to damage in various degrees. Pigments in paints and stains protect against UV rays, ultraviolet absorbers, while adding to the polyurethane varnishes and other (including "Spar" varnish) to work against UV rays. Polyurethanes are typically the most resistant to exposure to water, high humidity, extreme temperatures, and fungi or mold, which also adversely affect the performance of varnishes and paints.
Mouse pads 4.Computer
Polyurethane is used in the bottom of the number of mousepads.
5.Glue
Polyurethane is used as an adhesive, especially as glue for woodworking. Its main advantage over the tails of the more traditional wood is its resistance to water. It entered the North American market in general in the 1990s as Gorilla Glue and Excel, but long been used in Europe.
6.Wheels
Polyurethane is also used in the manufacture of solid tires. Modern and roller skating rink became economic only with the introduction of strong parts and abrasion-resistant polyurethane. Other structures have been developed for pneumatic tires, and variants microcellular foam are widely used in tires on wheelchairs, bicycles and other similar purposes. These types of foam latter are also widely found in car steering wheels and interior and exterior car parts, including bumpers and fenders.
7.Houses, sculptures and decorations
The walls and ceiling (not just insulation) of the futuristic Xanadu House were built with polyurethane foam. Vaulted ceilings and other irregular shapes are easier to make foam than with wood. Foam was used to construct odd-shaped buildings, statues and decorations in the Seuss Landing section of the theme park islands adventure. Specialty foam rigid foam produced by replacing the carved wood sold in the sign of industries and 3D topography.
8.Watercraft
Some surfboards are made with a solid polyurethane core. A rigid foam blank is shaped in the form of specifications, then covered with fiberglass cloth and polyester resin.
The hull of the Boston Whaler motorboat polyurethane foam is inserted into a fiberglass skin. The foam provides strength, buoyancy and muffle sound.
9.Construction Sealers and stop the fire
Head of Wall Firestop common: the pervasive presence demonstrates the need both operational and fire to test the compatibility between the joint sealant and mechanical / electrical through-penetrations. In other words, it is easier insist on the use of common firestops, which can also be used for seals penetration, otherwise it may be run by penetrating mechanical and electrical subtrades involuntarily cancel the fire resistance rating of the wall, which jeopardizes the entire fire safety plan in place of a building.
Head Wall Firestop Joint penetrated by both electrical and mechanical services, demonstrating the need for test operation and extinguishing of compatibility between the system against joint fire and penetrating, whether electrical, mechanical or structural.
Polyurethane sealants are available in 1, 2 and up 3 sets of hand, either in cartridge, pail or drum format. Polyurethane sealants are also sold for firestopping applications. Obviously, the sealant by itself provides no serious hindrance for the fire, as their bond easily the combustion of hydrocarbons. However, when backed by the inorganic insulation such as rock wool or fiber ceramic, which can act as an effective seal to prevent smoke and hose passage of current, especially in joints inorganic. It is, however, it avoid direct contact with liquid penetrant metal and penetration through the cables, as the heat carried by the piercing may endanger the sealant. This, however, requires much vigilance. In concrete to concrete, concrete or masonry joints, however, are free from sharp mechanical or electrical, that works well and reliably. Like all products and passive fire protection systems, the key to compliance with the code limit is demonstrable.
10.Tennis Grips
Polyurethane has been used to make several Tennis Overgrips as Supergrap Yonex, Wilson Pro Overgrip shaking and many others. These jaws are highly extensible to securely grip carefully sticks around the handle of the racket.
11.Electronic Components
Often electronic components are protected the influence of environmental and mechanical shock by enclosing them in polyurethane. Typically polyurethanes are selected for excellent abrasion resistance, good electrical properties, excellent adhesion, impact resistance, and flexibility at low temperatures. The disadvantage of polyurethanes is the limited upper service temperature (usually 250 ° F (121 ° C)). In the electronics manufacturing production would be buying two part urethane (resin and catalyst) is mixed and poured over the assembly of the circuit (see casting resin). In most cases, the final assembly of the circuit would be irreparable after the cured polyurethane. Due to its physical properties and low cost, polyurethane encapsulation (potting) is a popular choice in the automotive manufacturing sector in automotive circuits and sensors.
12.Bookbinding Industry
Power on the way to a new and better glue for bookbinders, a new adhesive system first introduced in 1985. The basis of this system is polyester or polyester, while the polyurethane (PUR) is used as prepolymer. Its special feature is the coagulation temperature and reaction to moisture.
1st Generation (1988 at the drupa) – Low starting solidity – high viscosity – the drying time of more than 3 days
2nd generation (drupa 1996) – Low starting solidity – High viscosity – Drying time of less 3 days
3rd Generation (2000 at the drupa) – Good starting solidity – Low viscosity – Drying time between 6 and 16 hours
4th generation (present) – Good starting solidity – from very low viscosity – Drying time is reached in a few seconds due to Dual-Core-Systems
Advantages of polyurethane glue in the industry of binding: PUR is a marvel compared to hot melt and cold glue. Due to lack of moisture in the tail, documents with fiber direction wrong can be easily edited. Even supercalandered printed and can be bound without problems. It is the most economical glue with an application thickness 0.01 mm theoretical. But in reality, it is possible to apply less than 0.03 mm. The polyurethane adhesive is weather resistant and stable at temperatures of -40 ° C to 100 ° C.
13.Watch Band adjustment
Polyurethane is used as a wrapper for bracelets black clock on the main material, usually stainless steel. It is used for comfort, style and durability.
href = "http://www.foam-cut.com/foam1.htm">
About the Author
moon gel practice pad workout
|
|
Custom LeatherCraft G350 Injected Gel Kneepads with Removable Caps $39.99 INJECTED GEL KNEEPADS W/REMOVABLE CAP – Removable snap-on/snap-off cap ~ For rough or delicate surfaces ~ Gel interior moves with knee for ultimate comfort ~ Breathable neoprene lower strap ~ Double closure system ~ Molded interior padding ~ Better fit & protection around knee ~ One size fits all… |
|
|
Custom LeatherCraft G352 Injected Gel Kneepads $22.00 Sold as each. One size fits all. 13-3/4″ x 4″ x 7-1/8″. Injected gel interior that moves with your knee. Double straps with buckle style fastening system. Molded interior padding. Grooved cap design prevents thread abrasion. Boxed . Manufacturer’s number: G352. Country of origin: China. Distributed by Clc/Custom Leather Craft…. |
|
|
Impacto 400-00 Gel Palm Anti Vibration Glove Medium Anti Vibration Anti Impact glove by Impacto. Black leather palm. Gel padding in the palm and index finger. Wrist tab with hook and loop closure. Provides abrasion and impact protection. Open back for cool comfort…. |
|
|
Pedifix Visco-Gel Moleskin Pedifix Protective Padding – 2 per Pack $6.59 INDICATIONS: This self adhesive gel cushion protects and moisturizes skin while absorbing pressure and friction. Its innovative Visco GEL releases mineral oil to soothe skin during use. Great for corns, calluses, bunions, blisters…. |
|
|
Pedifix Visco – Gel Moleskin Protective Padding $9.99 Gel ‘Moleskin’ self-adhesive sheets absorb pressure and friction. Easily cut to fit any area of the foot to help prevent and ease pain from common conditions. 100% medical grade silicone is hypoallergenic, durable, and will not flatten from repeated use. 4-way stretch, low friction anti-microbial fabric cover. Scissor trim to customize. 2.5 x 3 sheets, 2 per pack. Medical-grade Silicone cushions, … |
|
|
Visco-GEL Gel Moleskin Protective Padding $6.85 This self-adhesive gel cushion protects and moisturizes skin while absorbing pressure and friction. Its innovative Visco-GEL releases mineral oil to soothe skin during use. Great for corns, calluses, bunions, blisters, balls-of-feet and heels. Features Trim to any size |
|
|
Leather-Like Gel Mouse Pad with Wrist Rest $19.99 Mouse Pad with Precise Battery Saving Mousing Surface extends battery life of wireless mice up to 75%. Includes incredibly soothing gel wrist rest which encourages neutral wrist posture. Clear gel is easy to keep clean. Fun design brightens up your workspace. Also try Gel Wrist Rests for Keyboards…. |
|
|
Avenir Comfy Gel Cycling Gloves Avenir by Raleigh is the premier bicycle accessory line from legendary Raleigh Bicycles…. |
|
|
Canari Mens Mountain Trail Gel Baggy Shorts $50.00 Canari’s Mountain Trail Baggy Shorts are the perfect answer for the ride, anytime. The loose outershort is made using a soft, yet tough nylon talsan fabric that resists abrasion and fading. An 10″ inseam offers just above the knee coverage. The integrated cycle liner is made with a lightweight, wicking polyester flatback mesh fabric that keeps you cool and dry as you sweat. Soft touch gripper elas… |
|
|
Pearl iZUMi Women’s P.R.O. Pittards Gel Glove $40.00 Pearl Izumi Women’s P.R.O. Pittards Gloves. Comfort Bridge Gel padding relieves pressure on Ulnar and Median nerves for riding comfort and superior durability Pittards WR100X Natural Carbon Leather provides superior softness and durability Easy-Off glove removal tab Direct-Vent mesh ventilates while providing UPF40+ sun protection Bamboo carbon mesh palm lining enhances dry time and anti-odor prot… |