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Top 10 Injection Molding Companies in USA

Today’s injection molding industry in the United States has dramatically developed into a highly competitive and innovative manufacturing sector. As a key technology for converting plastic materials, injection molding is close to being a generic process that can effectively produce intricate parts economically. Injection molding is utilized in multiple industries, which include the automotive and aerospace industries, medical industries, and packaging industries to name but a few; injection molding is vital in industries where manufacturing includes large production of car parts, aerospace parts, and even the production of devices such as syringes and packaging materials. The United States houses some of the best and most efficient injection molding companies that provide advanced technologies, environmentally friendly methods, and virtually endless expansion of services.

In the following companies, the skills in mold design, parts prototyping, CNC machining, and final assembly are integrated to provide high-quality parts and products. They employ automation, robotics, and CAD to reduce time, improve efficiency on the production line, and improve quality. Also, today’s leaders are determined to achieve sustainability by promoting environmentally friendly materials and energy conservation even in the production line. Here are many options for prototype and machining manufacturers, first or second-tier suppliers, full-service high-volume production manufacturers, or custom parts manufacturers.

In this article, you will read about the 10 injection molding companies in the USA, their specialization, services, and roles in the industry.

1.  Murray Plastics

Year of establishment: 1998
Number of employees: 250-299
Business type: Plastic Injection Molding Services, Parts, and Mold Manufacturing Company.
Address: 1922 Old Candler Rd, Gainesville, GA, United States, Georgia

Website and Contact

Website: MurrayPlastics.com
Email: bill@murrayplastics.com
Phone: +1 770-297-7000

Company Profile

Murray Plastics is a manufacturer from the USA that has been dealing in injection molding and mold building services since it was established in 1998. Founded in Gainesville, Georgia, the company deals with the electronics and packaging sectors, including design engineering, tooling, and production. Specializing in thermoplastics and polyurethane, they provide excellent parts with a state-of-the-art molding process. Proudly supporting local manufacturers, Murray Plastics offers practical solutions at a superior value, including transport and timely delivery across various sectors.

Services

·         Plastic Mold Design and Engineering

·         Plastic Injection Molding

·         Injection Mold Building

·         Prototype Development

·         Quality Control and Testing

Pros

1. Energy Saving – The product reduces energy consumption when manufacturing plastic components.
2. Custom Solutions – Prescribes unique designs and choices of materials that would fit different uses.
3. U.S.-Based Manufacturing – Provides for faster production and delivery with a local support guarantee.

Cons

1. Fixed Cost – Creating a tool and mold may initially sound pricey.
2. Mechanical Limitations – Cannot be used with materials that have crystalline structures.
3. Volume Dependency – It is not that cheap at low volumes.

2. MSI Mold

Year of establishment: 2005
Number of employees: 51-200
Business type: MSI Mold company provides plastic injection molding services, CNC machining service, mold making service, prototype service and custom plastic parts service.

Website and Contact

Website: www.msi-mold.com
Email: sales@msi-mold.com
Address: 2045 S. Almont Ave, Imlay City, MI 48444
Phone: (248) 870-3039

Company Profile

MSI Molding is a high-quality plastic injection molding company specializing in offering company-specific applications in the automotive, electronics, and medical device industries. The company now works with modern technology and sophisticated equipment to facilitate engineering processes. Like most injection molding processes, plastic is advantageous in terms of high production volume and efficiency, material flexibility, and cost-effectiveness in generating intricate prototypes, short-run manufacturing of complex designs, and varied uses across industries.

Services

  • Plastic injection molds
  • Custom injection molding
  • Prototype injection molding
  • Design and engineering
  • Assembly and extras

Pros

1. The best choice for intricate designs for the highest levels of accuracy.
2. Cost-effective, mainly when used to produce many products, thereby maintaining standardization.
3. Multi-functional, accommodative to various materials and uses.

Cons

1. A high initial cost of creating the mold.
2. Are typically confined to particular kinds of materials.
3. Higher minimum number of parts per batch that it can manufacture and a longer setup time for small production runs.

 If you require plastic injection molding services in the USA, please call MSI Molding now.

3. UNIVERSAL PLASTIC MOLD

Year of establishment: 1972
Number of employees: 200-300
Address: Office Address: 13245 Los Angeles St, Baldwin Park, CA, United States, California
Business Type: Universal Plastic Mold (UPM) is in large-part plastic injection molding, plastic molding tools, assembly, and supply or transportation, mold maintenance etc.

Website and contact

Website: https://www.upminc.com
Phone: 1-888-893-1587
Phone: +1 626-962-4001
Email: sales@upminc.com

Company Profile

Universal Plastic Mold (UPM) is a California-based company ranked among the top leaders in plastic injection molding. It has been in the industry for over five decades and has acquired an ISO certification. UPM runs all year, performing different functions like prototyping, designing tools, assembling, and delivery. The finishing process manufacturer of automotive, medical, packaging, and solar implements, UPM features versatile capabilities. They are family-owned with a focus on quality and efficiency whilst offering over 80 products successfully launched in the market.

Services

  • Tooling and plastic fabrication
  • Plastic custom injection molding
  • Assembly services
  • Water injection
  • Program Management
  • Plastic Mold Repair Maintenance

Pros

1. 51-plus years of experience providing unique custom plastic injection molding.
2. Full-scope services provide within-house solutions to reduce the production and supply cycle.
3. Round-the-clock services and state-of-the-art equipment for multiple sectors. 

Cons

1. Specializing in medium and large part molding, with reduced capacity for small molding works.
2. If machinery is highly dependent on then there might be a rise in maintenance costs.
3. Like any other established plastic manufacturer, there is competition in the market.

If you are searching for plastic injection molding manufacturing in the USA, please visit Universal Plastic Mold.

4. The Rodon Group

Year of establishment: 1956
No or employees: 100-150
Business type: Sophisticated production, molds making, corporate responsibility, quality assurance, affordability, and polymers industry specialization.

Website and contact

Website: https://www.rodongroup.com
Phone: +1 215-822-5544
Email: sales@rodongroup.com
Address: 2800 Sterling Dr, Hatfield, PA, United States, Pennsylvania

Company Profile

The Rodon Group was established in 1956 in Hatfield, Pennsylvania, and is a family business specializing in plastic vertical injection molding and operating a 125,000-square-foot ISO 9001: This 2015 certified landfill-free facility contains over 125 runs, producing billions of parts yearly. Operating in mold design and manufacturing, tool making, and short-run, high-volume production for industries like Medical and Consumer Products, they focus on customers’ sustainable advantage, leveraging precise, cost-effective, and environmentally sound solutions for various manufacturing requirements.

Services

  • Plastic injection molding
  • Manufacturing
  • Tool making
  • Material selection
  • Large-scale production of lightweight plastic components
  • Production involves custom plastic injection molding
  • Little or no usage of landfill for disposal

Pros

1. ISO 9001: Maron is also 2015 certified, thus passing high quality standards of the company.
2. Operations free from using landfills, focusing on environmentally friendly processes.
3. The level of competition in the domestic markets removes the essence of sourcing products from other countries.

Cons

1. It is restricted only to large-scale production and avoids small-scale production.
2. Tooling and mold design costs are among the highest for green electronics at the beginning of implementation.
3. This is various because it is confined to industries that fit the injection molding methods.

If you need plastic injection molding services in the USA, visit The Rodon Group!

5. Plastimold Products

Year of Establishment: 1998
Number of employees:50-100
Business type: Specializing in providing building injection molding services, product design, prototype, mold manufacturing, mechanical assembly, and material sourcing.

Website and contact

Website: https://plastimoldproducts.com
Email: hello@plastimoldproducts.com
Phone: +1 561-869-0183
Address: 250 N Congress Ave, Delray Beach, FL, United States, FL

Company Profile

Plastimold Products is a company engaged in plastic injection molding founded in Delray Beach, Florida, U.S.A, in 1998. The company offers design services, such as creating molds, prototyping, and assembly. They run a hi-tech, ISO-compliant factory day and night for their production, which is focused and environmentally friendly. Plastimold produces for industries such as medical, aerospace, and consumer goods to provide dependable value-for-money solutions and be a reliable manufacturing partner in the global market.

Services

  • Plastic injection molding
  • Plastic product design
  • Inert molding
  • It is also called over molding injection molding
  • Mold transfer management
  • Prototyping
  • Assembling

Pros

1. An authorized production center provides good quality and accuracy as it complies with the requirements of ISO standards.
2. The fact that automated processes run around the clock makes them more productive and less expensive.
3. A wide range of industries specializing in services that require complex mechanics, such as health, aviation, and manufacturing industries, with manufactured products that include consumer goods.

Cons

1. This suggests that high-volume production is not ideal for small-demand situations.
2. It is also important to note that while setting up a mold project, an individual might incur vast sums to create it.
3. Well-suited operations may not necessarily provide services for other manufacturing that is non-plastic.

To get the best services in plastic injection molding, contact Plastimold Products!

6. Hi-Tech Mold & Engineering, Inc.

Year of Establishment: 1982
Number of employees: 300-400
Business type: This company provides plastics and tooling services throughout the mold design, machining, molding, and assembly processes.

Website and contact

Website: https://www.hitechmold.com
Email: employment@hitechmold.com
Phone: +1 248-852-6600
Address: 2775 Commerce Dr, Rochester Hills, MI, United States, Michigan

Company Profile

Hi-Tech Mold & Engineering, founded in 1982 in Rochester Hills, Michigan, supplies products and services for the plastics and tooling industries. Operating in mold design and manufacturing, CNC turning and milling, 3D printing, injection molding, and assembling, the company works with the automotive, aerospace, and medical industries. Certified to IATF 16949 and ISO 9001: In 2015, Hi-Tech set strategic goals focusing on innovation, quality, and improvement to provide the highest quality solutions developed in the technologically advanced center.

Services

  • CNC Machining
  • Additive Manufacturing
  • Plastic parts through Injection Molding
  • Value-added assembly
  • Product design and development

Pros

1. Certified to IATF 16949 and ISO 9001: In 2015, achieving the highest quality of services became the foremost priority.
2. Provides coverage from mold design to added-value assembly services.
3. It involves various sectors, such as the automobile, aviation, and healthcare industries.

Cons

1. Specialization tends to bar more fantastic applications to other areas or organizations.
2. High initial costs of creating molds for creating the molded articles.
3. Not cost-effective or efficient for companies with low volume demands for their product.

Are you seeking new plastics and mold tooling ideas? Hi-Tech Mold is the right company you need to contact.

7.  Bennett Plastics

Year of Establishment: 1982
Number of employees: 80-200
Business type: Specializing in designing, manufacturing, molding and assembling, injection molding plastic products and packaging.

Website and contact

Website: https://www.bennettplastics.com
Email: info@bennettplastics.com
Phone: +1 973 684 1501
Address: 22 Kentucky Avenue, Paterson, New Jersey 07503

Company Profile

Bennett Plastics, which started in 1982 in Paterson, New Jersey, offers plastic injection molding services. The company has more than 40 years of experience and specializes in product design, engineering, mold making, and assembling designed products. Using the state-of-the-art equipment, they offer services ranging from 75-500 tones and assure quality and accuracy. Reporting to consumer goods, electronics, and medical devices, Bennett Plastics focuses on sustainability, customer services, cost-effectiveness, and quality in manufacturing its custom-designed, value-added plastic parts.

Services

  • Specialty Plastic/Medical and Orthopedic / Injection Molding
  • Both Product Design and Engineering
  • Mold Making and Maintenance
  • Assembly and Packaging
  • Further Processing Services/Services after Labeling

Pros

1. Practical experience in injection molding processes of over 40 years.
2. Sophisticated tools make the work as accurate as possible and the products as high quality as possible.
3. Full service from architecture to packs from one umbrella.

Cons

1. Small to medium-scale projects may not be an issue, but massive projects may be hampered by limited machine capacity (75-500 tons).
2. Concentration on plastics eliminates other manufacturing materials.
3. The necessity of the investments when creating individual molds.

If you need sound plastic injection molding services, visit Bennett Plastics now.

8. PlastiCert, Inc.

Year of Establishment: 1981
Number of employees: 50-100
Business type: Custom plastic injection molded providing services in the design & manufacturing of molds, over-molding, and added services.

Website and contact

Phone: +1 507-523-2300
Website: https://www.plasticert.com
Email: lewiston@plasticert.com
Address: 300 Wilson St N, Lewiston, M, N United States, Minnesota

Company Profile

PlastiCert Inc., founded in 1981 and located in Lewiston, Minnesota, offers custom plastic injection molding services. Having capabilities in mold design, insert molding, over molding, and secondary operations/plastics assembly, PlastiCert serves sectors such as aviation, telecommunications, and heating/ventilation/air conditioning (HVAC). ISO 9001: Incorporated in 2015 and UL registered, the company values quality and creativity. PlastiCert has been in the business of providing OEMs with reliable plastic molding services for over 40 years.

Services

  • Plastic Injection Mold, Special Plastic Injection Mold
  • Mold Design and Development
  • Insert Molding
  • Over molding
  • Decoration and Electro-Mechanical Assembly as Value Added Services

Pros

1. More than 40 years of experience in plastic injection molding.
2. ISO 9001:It has been certified since 2015 to verify the company’s quality standards.
3. Manufacturing services: facilities ranging from simple mold design to over molding and other additional assembly services.

Cons

1. Designed for moderate and low production capacities, which prevents the company from handling large scales.
2. Mentioned to focus predominantly on particular sectors, which minimizes the field of its use.
3. The options often come with higher initial costs in the tooling and design of the parts.

If you need the best and most affordable plastic injection molding service, PlastiCert is the right choice!

9. LS Hardware Tech Co., Ltd

Year of establishment: 2008
Number of employees: 200-300
Business type: International manufacturer of prototypes and Precision parts through milling services and injection molding.

Website and contact

Website: https://www.lsrpf.com
Email: info@longshengmfg.com
Phone: +15168866992
Address: USA

Company Profile

Located in Shenzhen, China, with an operation center in California, USA, Longsheng Manufacturing (LS) specializes in prototype and short-run production. Operating 3D printing, CNC machining, metal fabrication, and injection molding services, LS caters to the automotive, aerospace, and medical device manufacturing industries. Certified with ISO 9001:ISO 13485:2015, ISO 13485:2015, AS9100D, LS leverages innovative technology, rapid turnaround, and worldwide presence to provide accurate, affordable manufacturing services accompanied by outstanding customer service.

Services

  • CNC machining
  • Injection molding
  • Metal casting
  • 3D printing
  • Rapid prototyping
  • Surface finishing

Pros

1. Source of production in China and availability of local support in the USA.
2. Relatively a short lead time with the possibility of starting production from one business day.
3. Computer-controlled machining methods, additive manufacturing technologies, and injection molding.

Cons

1. Its methods of managing international operations can bring some complexity to supply chains.
2. It may, however, reduce its appeal, especially with small or niche firms.
3. Costs may be higher when a solution has been tailored and made.

If you want consistent injection molding solutions, Longsheng Manufacturing is the right solution provider globally.

10. Sincere Tech

Year of establishment: 2005
Number of employees: 50-200
Business type: Commercial plastic injection mold maker, die-cast mold maker, mold maker for RTV silicone rubber, product assembly services, prototype maker, and manufacturer.

Website and contact

Website: www.plasticmold.net/
Email: info@plasticmold.net
Phone: +86 135 30801277
Address: ChangPing, Dongguan City, Guangdong Province, China

Company Profile

Sincere Tech, located in Dongguan City, Guangdong Province, China, specializes in producing plastic injection mold, die casting mold, and silicone rubber mold for the electronics manufacturing industry since 2005, established by Mr. Wang Lei. The company’s manufacturing specializations are mold design, prototype manufacturing, and assembly. Certified in ISO 9001: Environmental Endorsement Standards: 2015; Sincere Tech Standard: ISO 14001, New Car QC Standard: ISO 14001:2015, Automotive Industry Technical Standard: IATF 16949, Sincere Tech Business scopes involve automotive, medical, and electronic industries to bring innovation, high quality, and customer-oriented service to the global market.

Services

  • Plastic Injection Molded Products
  • Die Casting Molds
  • Silicone Rubber Molding
  • Prototyping Service
  • Full Product Assembly
  • Mold Design and Manufacturing
  • Product Packaging
  • Secondary operations include painting, printing, and welding, among others

Pros

1. The top-notch tier of custom mold products made from state-of-the-art technology with an emphasis on workmanship.
2. Certifications like ISO 9001:2015, ISO 14001:2015, and IATF 16949 in 2016 guarantee quality and compliance.
3. Designing the mold, producing the required parts, and assembling a complete product.

Cons

1. There is a risk of business with an extended delivery lead time for international clients since most manufacturing facilities are in China.
2. One disadvantage of establishing a form is that there are usually enormous fixed costs associated with constructing custom molds for large projects because of their size.
3. Most branches Lack direct client servicing outbound from the region.

So, if you want authentic custom mold manufacturing and assembling solutions, visit Sincere Tech.

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TPE overmolding

insert overmolding

Now is the time to start overmolding thermoplastic elastomers (TPEs). TPEs have traditionally been used to replace rubber, but new consumer market trends have made the overmolding idea a fact in the business world. Demand and trends in the consumer market are growing for better ergonomic feel and touch, grippability, looks, impact protection, vibration separation, and insulation. Consumer product designers are setting the standard for material makers to meet by coming up with solutions that look and feel good and work well in demanding end-use applications.

This essay talks about TPE overmolding technology in general terms and its as a group of materials that can be used to make designed solutions for this evergreen trend. In terms of rigid substrates, polypropylene (PP), polyethylene (PE), polystyrene (PS), high impact polystyrene (HIPS), polyphenylene oxide (PPO), glycol modified polyethylene terephthalate (PETG), Acrylonitrile Butadiene Styrene (ABS), and semicrystalline polar plastics like polyester (PET, PBT) and polyamide (Nylon 6, Nylon 66) are some examples. New technologies for mixing and compatilizing materials have made it possible to make goods that can be overmolded onto these different substrates.

overmolding

For TPE overmolded onto rigid surfaces, a lot of things are very important. The first and most important thing is to choose the type of TPE that will work with the rigid base. Also important are the overmolding process (such as insert or 2K Moulding), the type of machine, the process conditions, how the material is prepared, the design of the part and the design of the mould. Unique material technologies, new part and tool designs, and improvements in overmolding technologies will keep designers’ minds active so they can meet the constantly growing needs of consumers for comfort, good looks, and added value.

TPE Overmolding Technology

TPE Overmolding uses injection moulding to put one material (Over-Mold) on top of another material (Substrate). The over-molded material should stick to the substrate in a way that lasts in the end-use setting and works well. Over-molding gets rid of the need for glues and primers to attach TPEs to hard materials. Overmolding technology gives designers more freedom, lowers the cost of production, and makes it easier to make things. Multiple Material Moulding and Insert Moulding are the two main ways to do over-molding.

Injection moulding with more than one material is also known as multicolour or two-shot injection moulding. Figure 1 shows the kind of tools that are used. They have two or more injection units. The injection machine arms can be set up so that they are parallel to each other or at right angles to each other. There are two sets of holes in the mould. One set moulds the base material, and the other set moulds the covering material.

There are two steps to the two-shot moulding process. The first step is for the first barrel to fill the substrate’s set of holes. Once the substrate is cool, the mould opens and the side that can be moved turns 180° without the substrate coming out of the mould. Next, the mould is closed, and the over-mold material is injected into the second barrel. The second half of the mould is filled in on the side that stays still. If the over-mold material needs to be shaped on both sides of the part, the mould might move the parts between two sets of holes instead of turning.

Rotary Platen Machines vs. Rotary Die Machines: A rotary platen on the second part of the press is sometimes built into the machine to make it turn. When a rotary platen is used four times separately, mould halves that are mounted on it are typically used. There are times when the rotation is built into the tool itself, and there are only two mould halves but four sets of mould holes.

Moving: The tool in the Core process has a moving part that is powered by hydraulics or air. Once the first substrate has been injected and given time to cool, a mould section pulls back, making a space for the TPE over-mold material. The TPE is then introduced, most of the time from the side of the hole that is visible when the insert is pulled back. This method has faster cycle times, more cavitation, and better machine performance. The only problem is that only a constant thickness of TPE can be used.

insert overmolding

Insert Molding-insert overmolding

Insert molding is one of types of overmoldings, during insert moulding, a hard plastic substrate or metal part that has already been moulded is put into the hole by a robot or a person (Figure 2). The second material, called “over-mold,” is put on one side of the insert or around the whole thing other times. For insert moulding, standard injection moulding tools are used.

Rotate or move around? Table Moulding: A horizontal injection unit or a robot is used to shape a substrate or put an insert in the second cavity in the first position. The table moves or turns to the next station, where another horizontal or vertical injection unit is used to put the TPE in. You can use a hot sprue or put the runner at the splitting line. A third turn of the rotary unit’s table sends it to a “off-load” station, where the finished two-part part is ejected.

TPE Overmolding Process

Which of the possible processes and mould designs to use relies on the material chosen, the cost of labour, the tools and machines that are available, and the economics of making a lot of them. If the insert is not a thermoplastic, insert moulding has to be used. If you only need a small amount of the plastic or metal substrate, the cost of local labour is low, and you need to keep the cost of the tools low, you should place them by hand. For larger amounts of work, shuttle tools can be used. Robotically placed inserts and rotary table tools can be used when the amount of work needs to be done justifies the cost. If you need to make a lot of parts or the cost of labour is high where you live, two material moulding machines are best for plastic substrates. For the highest production numbers and the nicest-looking parts, hot runner systems with valve gates are best.

Overmolding Part Design Considerations

There are a lot of different parts to designing overmoldings, and this paper talks about some general things to keep in mind.

When it comes to materials, bondable TPEs have stricter rules than regular TPEs. The same is true for making parts. When designing two-part parts, you have to think about how the two different flexible materials will shrink, which is different from designing one-part parts. Both have their own gate and runner systems that need to be customised based on the features of the material being used.

To get the best cycle time, the thin walls of the base and over-mold should be as even as possible. In most over-molding situations, walls that are between 1 mm and 3 mm thick will join well. If the part needs thick areas, they should be cored out to keep the part from shrinking too much and to cut down on cycle time and weight. To avoid flow issues like back fills and gas traps, changes in wall thickness should be made slowly. Adding circles (at least 0.5 mm) to sharp corners can help lower stress in that area. Deep dark pockets or ribs that can’t be opened should be avoided. Long draws should have a draft of 3 to 5 degrees to help the ball get out. Deep undercuts can be made with over-mold compounds, but only if an advance core is used when the mould opens, the part doesn’t have any sharp edges, and the elastomer is allowed to bend as it comes out of the mould.

When moulded, most TPE compounds shrink a fair amount in the direction of flow but not much when moulded in the cross-flow direction. This could cause the over-molding material to shrink more than the substrate once the part is taken out of the tool. This can then cause the substrate part to warp or cup, generally in the direction of the flow of the overmolding material. In parts where the substrate is thinner than the over-mold or where a low stiffness substrate material is used, this is especially true. the parts should be long and thin. This can be partially fixed by using base materials with a higher modulus and adding stiffening ribs to the substrate. It will also help to use thinner coats and an over-mold grade with less hardness. Moving the gate to change the flow pattern of the TPE might also help.

Shore hardness, which is a material’s resistance to being dented on a 6.3 mm minimum thickness moulded plate (ASTM D2240), is used to measure TPE materials. An item with a lower hardness feels softer on the outside, even if it is the same thickness. But because overmolding is usually only done on the thin skin of TPE, the hard base below affects how soft it feels. If this is put through a hardness test, a smaller indenture will show that the rock is harder, even if the skin is soft. If the rubber over-mold is to be on both sides of the parts (A and B), two material moulds must be used that can move between mould sections.To make a smooth layer on a part or the whole side of a simple part, you should use two material moulds with moving cores. The output rate can be very high, depending on how thick the walls of the elastomer and the substrate are.

How TPE Sticks to Engineering Thermoplastic

There are many things that can change how well hard engineering plastic and soft rubber stick together. To build specific relationships between materials, it’s important that the surface energies of both of them are the same. The power of TPE to stick to a surface is another important factor. For certain reactions to happen between the TPE and the substrate, they need to be very close to each other and the surface needs to be wet. The way the TPEs theologize, as shown in Figure 3, determines how they wet out. Over-molding materials don’t have a very high viscosity. They are also sensitive to shear and show shear thinning behavior.

Below picture  shows that the viscosity is near the lower end of the range when the flow rate is high. This helps the TPE run into and fill thin-walled areas that are common in over-molding.

TPE over-molding

The chemistry of the TPE and the type of industrial plastic have a big effect on how well it wets. As well as the adhesion qualities, the elastomer’s diffusion and viscoelastic properties also play a role. The point where the TPE and stiff substrate meet is very important for both the bond strength and the type of failure, which can be either cohesive (C) or adhesive (A). When looking for signs of a strong bond, the cohesive system is usually thought to be the best way to tell. But a weak TPE with only moderate bond strength can make it look like the linking is strong. There are times when good bonding exists even when the glue fails. There are three types of processes at the contact that can help the rigid substrate and the soft thermoplastic elastomer stick together. These can be seen in below picture.

Overmolding part design guideline

Design is what makes mechanical connection possible. Not a real link is made between the two surfaces, but any TPE will work in this case. The second way works because the substrate and the overmolding TPE material are chemically compatible. Chemical compatibility is based on the surface energies, which are connected to how well the substrate and TPE stick together. When the moulding method and temperature are right, an interface can form where the molecules of the base and the overmold mix. You can make an interface with a styrenic TPE or an olefinic TPE that has been moulded onto polyethylene as the base. The third way can be built into the TPE. The bonding process is made up of specific polar interactions or chemical reactions between the groups of the TPE and the rigid substrate.

A “90-degree Peel Test” can be used to find out how strong the bond is between the TPE and the industrial plastic. We changed the ASTM D903 method for plastics to test how well soft TPE sticks to hard thermoplastic. A moulded base with a TPE skin insert moulded on top of it is used for the tests. An Instron tension tester is used to cut and pull a strip of TPE that is an inch wide at a right angle to the base. It is locked in place on the wheel so that the 90-degree angle stays the same while the rubber is being pulled. The adhesion strength is found by how hard it is to pull the elastomer away from the base. This force is usually over 2 inches. It is put into two groups based on whether it fails because of adhesive failure (A) or cohesive failure (C). Adhesive failure means that there is no TPE residue left on the material. The numbers given are the average of three different studies of adhesion. Because the customer wants a certain level of adhesion, we’ve decided that an adhesion number higher than 12 pli is good enough.

Today, there is a huge interest in overmolding TPEs onto rigid substrates, especially for market goods that need to have a soft touch. New TPEs are being overmolded onto a growing number of substrates. This gives designers more design freedom and the chance to make their goods stand out in a market full of “me-too” copies.

TPEs are very famous because they help with sales at the point of sale. People today have a huge selection of goods to choose from in stores, and companies that make goods want to make theirs stand out. There are many good reasons to pick a product with an TPE overmolding surface, such as new colours, textures, patterns, and comfort. For many people, a “warm” soft touch feels better than a hard plastic feel. And things that look and feel like rubber are often thought to be more valuable. People are smarter about finding goods that fit their bodies better and reduce vibrations now that they know more about ergonomics and the rise in joint overuse injuries. Overmolded TPEs can also be useful for things other than feel and usability. Some examples are providing a safe, strong grip in wet areas, waterproofing gaskets and seals, molded-in “bumpers” to protect against impact and prevent early breaking, and reducing vibration.

 

 

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