A 360-degree look at resin conveying systems: types, operation, economics, design, installation, components and controls.
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Combat the skilled labor shortage using this comprehensive resource to train your own plastics processing experts.
Deep dive into the basics of blending versus dosing, controls, maintenance, process integration and more.
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Learn about sustainable scrap reprocessing—this resource offers a deep dive into everything from granulator types and options, to service tips, videos and technical articles.
Second quarter started with price hikes in PE and the four volume engineering resins, but relatively stable pricing was largely expected by the quarter’s end.
While the major correction in PP prices was finally underway, generally stable pricing was anticipated for the other four commodity resins.
Despite price increase nominations going into second quarter, it appeared there was potential for generally flat pricing with the exception of a major downward correction for PP.
First quarter was ending up with upward pricing, primarily due to higher feedstock costs and not supply/demand fundamentals.
Despite earlier anticipated rollover in prices for most of the volume commodity resins, prices were generally on the way up for all going into the third month of first quarter.
While price initiatives for PE and PVC were underway, resin prices had rollover potential for first two months of 2024, perhaps with the exception of PET.
Resin drying is a crucial, but often-misunderstood area. This collection includes details on why and what you need to dry, how to specify a dryer, and best practices.
Take a deep dive into all of the various aspects of part quoting to ensure you’ve got all the bases—as in costs—covered before preparing your customer’s quote for services.
In this collection of articles, two of the industry’s foremost authorities on screw design — Jim Frankand and Mark Spalding — offer their sage advice on screw design...what works, what doesn’t, and what to look for when things start going wrong.
In this collection, which is part one of a series representing some of John’s finest work, we present you with five articles that we think you will refer to time and again as you look to solve problems, cut cycle times and improve the quality of the parts you mold.
Gifted with extraordinary technical know how and an authoritative yet plain English writing style, in this collection of articles Fattori offers his insights on a variety of molding-related topics that are bound to make your days on the production floor go a little bit better.
In this three-part collection, veteran molder and moldmaker Jim Fattori brings to bear his 40+ years of on-the-job experience and provides molders his “from the trenches” perspective on on the why, where and how of venting injection molds. Take the trial-and-error out of the molding venting process.
Mike Sepe has authored more than 25 ANTEC papers and more than 250 articles illustrating the importance of this interdisciplanary approach. In this collection, we present some of his best work during the years he has been contributing for Plastics Technology Magazine.
In this collection of content, we provide expert advice on welding from some of the leading authorities in the field, with tips on such matters as controls, as well as insights on how to solve common problems in welding.
Mold maintenance is critical, and with this collection of content we’ve bundled some of the very best advice we’ve published on repairing, maintaining, evaluating and even hanging molds on injection molding machines.
Thousands of people visit our Supplier Guide every day to source equipment and materials. Get in front of them with a free company profile.
NPE2024: Lowering barriers to additive manufacturing adoption in toolmaking.
Allegheny Performance Plastics turned to 1factory's cloud-based manufacturing quality control software for streamlined, paperless quality systems.
To design the best mixers for single screws, you must completely understand how polymer moves through a mixer channel or groove.
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At NPE2024, Novatec moves to rewrite the rules for material conveying with patent-pending smart-pump technology.
While the major correction in PP prices was finally underway, generally stable pricing was anticipated for the other four commodity resins.
With no minimum order and an impeccable record of on-time delivery, Precision Color Compounds is becoming a force in the color masterbatch business.
Thermosets were the prevalent material in the early history of plastics, but were soon overtaken by thermoplastics in injection molding applications.
After a six-year hiatus, this year’s show was a resounding success, with meaningful technologies on display that will help processors run their businesses more efficiently.
Key factors for the progress are innovative materials, advanced automation and precision engineering.
Topping five other entries in voting by fellow molders, the Ultradent team talks about their Hot Shots sweep.
Serendipitous Learning Opportunities at PTXPO Underscore the Value of Being Present.
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Ultradent's entry of its Umbrella cheek retractor took home the awards for Technical Sophistication and Achievement in Economics and Efficiency at PTXPO.
technotrans says climate protection, energy efficiency and customization will be key discussion topics at PTXPO as it displays its protemp flow 6 ultrasonic eco and the teco cs 90t 9.1 TCUs.
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Line features a single touchscreen for easy setup and operation.
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NPE2024: Dukane’s new Ultrasonic Thin Wall welding system is well suited for welding applications of PP to PP TD25 painted parts.
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Noting that geopolitical changes require new corporate strategies, European plastics and rubber machinery trade groups announced that incoming orders fell 22% in 2023.
System tracks, controls and saves everything from material recipes to process parameters, operator activity from logging on to start, to emergency stops and more.
Mixed in among thought leaders from leading suppliers to injection molders and mold makers at the 2023 Molding and MoldMaking conferences will be molders and toolmakers themselves.
After successfully introducing a combined conference for moldmakers and injection molders in 2022, Plastics Technology and MoldMaking Technology are once again joining forces for a tooling/molding two-for-one.
Multiple speakers at Molding 2023 will address the ways simulation can impact material substitution decisions, process profitability and simplification of mold design.
When, how, what and why to automate — leading robotics suppliers and forward-thinking moldmakers will share their insights on automating manufacturing at collocated event.
As self-imposed and government-issued sustainability mandates approach, injection molders reimagine their operations.
August 29-30 in Minneapolis all things injection molding and moldmaking will be happening at the Hyatt Regency — check out who’s speaking on what topics today.
Get your clicking finger in shape and sign up for all that we have in store for you in 2023.
Molding 2023 to take place Aug. 29-30 in Minnesota; Extrusion 2023 slated for Oct. 10-12 in Indiana.
Join this webinar to learn about Conair's patented Conveying with Optimizer system, which utilizes artificial intelligence (AI) to overcome resin conveying issues automatically. Conveying with Optimizer uses valves, remote sensors and AI to eliminate conveying challenges that operators face daily throughout the plant. With this new fully-retrofittable solution, interruptions like clogged filters, air leaks, changes in density or distance, moisture changes, and operators making manual adjustments can all be eliminated with Conair's Conveying with Optimizer. Agenda: What exactly is Conveying with Optimizer? What are the benefits of using Conveying with Optimizer? What problems does Conveying with Optimizer overcome? How to upgrade your system
Cooling time is typically the longest step of the molding process. How can you make it more productive? Learn how cooling time can be turned into production time by running two molding processes simultaneously on a single molding machine. For longer cycles, this can mean twice the productivity. In this webinar, you'll learn more about the Shuttle Mold System and how to calculate its potential productivity impacts for your application. Agenda: Learn how the Shuttle Mold System can deliver value to your business See the recent technical updates made to the system Calculate the potential impact on productivity
Discover possible applications in large format printing including layup tools, transport modules, film fixation devices, design components and enclosures. These are used in various industries such as automotive, aerospace, architecture and many others. Agenda: Possible applications in large format printing: layup tools, transport modules, film fixing devices, design components and enclosures. Process reliability and component quality in component production Pros and cons of the technology Sneak peek into current development projects—What will the large format printing of tomorrow look like?
In this webinar, Cold Jet will discuss some of the ways processors use dry ice such as in-machine mold cleaning at operating temperatures, de-flashing or de-burring parts, improving OEE scores, extending mold life, cleaning parts before painting, post-processing 3D printed parts, lowering GHG emissions, and monitoring and reporting the process. Agenda: Cold Jet Overview & Dry Ice 101 Understanding the Process and Fine-Tuning Techniques Case Studies: Applications in Plastics Monitoring the Process Exploring the Importance of Dry Ice Cleaning in an ESG Era
Finding it hard to get technical talent? Experiencing the pain of a knowledgeable, long-term employee's retirement? Learn how plastics processors are training generative AIs on their operations and unlocking the value from their tribal knowledge. Plastics processors are training generative AI models on their operations — from machine manuals to tools, polymers, procedures, maintenance records and engineering projects. Applying generative AI in the right ways can lower plastics processors' costs, improve overall equipment effectiveness (OEE) and upskill teams. In this webinar, you'll learn how to deploy AI technical assistants to your teams, what works and what doesn't, and how to use AI to build an organization that never loses tribal knowledge and fosters inter-team collaboration. Agenda: What is generative AI and how can its cognitive abilities be applied to plastics? Case study: how an injection molder trained a large language model on manuals and maintenance records to reduce downtime Case study: using generative AI in engineering teams to improve product development Live demonstration of a generative AI deep-trained on plastics knowledge Looking to the future: five predictions for an AI-augmented workforce in plastics
Turnaround time can be as low as 24 hours, although two or three days might be more typical. Rapid prototyping like this is especially useful to quickly identify critical end-use part geometries that will work in the molding process. Key components include material choice, 3D printing technology selected, use of adaptable mold bases for the mold inserts and implementation of appropriate injection molding process conditions. This presentation will review work conducted toward the assessment of a high-stiffness, high-temperature-resistant ceramic modified urethane acrylate for injection molding inserts. Agenda: Guide for 3D-printed injection mold inserts Optimization of digital light processing (DLP) printing Compatibility with various thermoplastics Real-world application success stories
Debuting in 2010, the Parts Cleaning Conference is the leading and most trusted manufacturing and industrial parts cleaning forum focused solely on delivering quality technical information in the specialized field of machined parts cleansing. Providing guidance and training to understand the recognized sets of standards for industrial cleaning, every year the Conference showcases industry experts who present educational sessions on the latest and most pressing topics affecting manufacturing facilities today. Discover all that the 2022 Parts Cleaning Conference has to offer!
Presented by Additive Manufacturing Media, Plastics Technology and MoldMaking Technology, the 3D Printing Workshop at IMTS 2024 is a chance for job shops to learn the emerging possibilities for part production via 3D printing and additive manufacturing. First introduced at IMTS 2014, this workshop has helped hundreds of manufacturing professionals expand their additive capabilities.
Formnext Chicago is an industrial additive manufacturing expo taking place April 8-10, 2025 at McCormick Place in Chicago, Illinois. Formnext Chicago is the second in a series of Formnext events in the U.S. being produced by Mesago Messe Frankfurt, AMT – The Association For Manufacturing Technology, and Gardner Business Media (our publisher).
Most thermoset molding processes still treat the mold like a black box where the curing process is invisible and mysterious, and nobody knows what is happening to the material until the mold opens. That just isn’t so.
In last month’s installment, we briefly discussed using torque rheometry as a way of monitoring and measuring the change in the viscosity of a thermoset material as it goes through the process of softening, gelation and crosslinking. This is a useful tool for characterizing the curing process, evaluating lot-to-lot consistency, and capturing the effects of temperature on the curing profile.
But another tool offers even more insight into this process and captures the interaction between time and temperature as they both influence the process of establishing a crosslinked structure. This tool is dynamic mechanical analysis (DMA). It can be performed on a variety of instruments, including a parallel plate or a cone-and-plate configuration.
The raw material is placed between these two elements and then one side of the system undergoes a regular, periodic rotation while the material is heated. The periodic rotation enables the simple measurement of torque to be resolved into the elastic modulus measured in shear, referred to G’, and the viscous modulus, G”. These two properties can be used, in turn, to calculate a property known as tan delta (G”/G’) as well as the viscosity of the system. The complex viscosity, is expressed as:
Figure 1 shows a close-up view of the early portion of such an experiment, plotting the complex viscosity and tan delta of the material as a function of rising temperature. This focuses on the early stages of the change in the material as it is heated and the viscosity declines to a minimum value before turning higher as the crosslinking process begins. As the viscosity rises, tan delta declines rapidly, indicating the early stages of curing. Lower tan delta values are associated with a stiffer, more rigid and less compliant material.
FIG 1 Close-up view of the early portion of a DMA, plotting the complex viscosity and tan delta of the material as a function of rising temperature. Source: Mike Sepe
These experiments can also be run at constant temperatures to examine the effect that temperature has on the time required to reach a stable degree of crosslinking. These lab experiments can then be used to provide guidance for how to set the mold temperature in a manufacturing process so that parts with optimal structure and properties are obtained.
Figure 2 shows the results from such an experiment. In this case, an unsaturated polyester known as a bulk molding compound (BMC) was heated to three different temperatures and the viscous and elastic modulus of the material was monitored as the material crosslinked. Note that the vertical axes are plotted logarithmically to capture the very large change these properties undergo as curing takes place.
When the material is in the pre-cured state, the properties are dominated by the viscous fluid phase while the elasticity is the minor component. In this state, the material is soft and compliant, deforming readily under the influence of an applied force such as that supplied by a compression mold closing on a charge of the material placed into the tool. The reduction in viscosity associated with the heating in the mold enables the material to flow through the mold.
FIG 2 An unsaturated polyester known as a bulk molding compound was heated to three different temperatures and the viscous and elastic modulus of the material was monitored as the material crosslinked.
As heating continues, the crosslink structure begins to develop. This is indicated by an increase in both the elastic and viscous modulus. However, the elastic modulus increases more rapidly, indicating the material is increasing in stiffness and decreasing in its ability to flow as the viscosity increases. At some point, the two curves cross, and this crossover point is often referred to as the gel point. Many treatments of this behavior identify this crossover as the point where the viscosity become high enough so the material will resist continued flow.
Optimizing the molding process involves balancing the effects of the viscosity increase with the rate of crosslinking.
Research performed by Horst Henning Winter and colleagues between 1986 to 1991 defines this point in a much more sophisticated and precise manner. However, it is evident — regardless of which interpretation is used — that as the elastic phase becomes more dominant and the viscous phase becomes less of a factor, the viscosity will rise to a point where continued flow becomes impossible. The mold cavity should be full before this point is reached or the result can be incomplete fill, poor weld line strength, porosity and cosmetic defects sometimes referred to as hard spots.
Optimizing the molding process involves balancing the effects of the viscosity increase with the rate of crosslinking. If the mold temperature is too high and the rate of compound distribution is too slow, then the above mentioned problems may be the result. But if the mold temperature is too low, then the material may need to held in the tool longer to achieve the appropriate degree of crosslinking.
These crossover points are denoted in Figure 2 and it is evident that as the temperature the material is exposed to increases, the time required to reach this point decreases. Figure 3 plots the relationship between temperature and time of gelation, and this can be extrapolated to predict the effects of changing the temperature. But there is additional data that can be extracted from the curves in Figure 2.
FIG 3 The relationship between temperature and time of gelation can be extrapolated to predict the effects of changing the temperature.
The plateau value for elastic modulus is a relative indication of the degree of crosslinking, and it can be observed that this plateau is influenced by the curing temperature. While higher temperatures do produce faster achievement of a crosslinked structure, this rapid development of the rigid state can hinder molecular mobility in the later stages of curing, leading to a reduced level of crosslinking in the final product. This illustrates the intricate relationship between time and temperature on the final structure of the product. It is interesting to note the difference between the elastic modulus at the start and the conclusion of the experiments. For this material, the difference is almost two orders of magnitude or a factor of nearly 100.
In the late 1980s, an alternative technique for cure monitoring was developed known as dielectric analysis (DEA). This method is similar to DMA, but instead of imparting a periodic mechanical input to the material, it uses a periodic electrical signal that causes the ionic constituents in the material to oscillate. This motion is detected and measured as ionic mobility, which is high in the pre-cured raw material and becomes increasing constrained as the crosslink structure develops.
While DEA was initially used as a benchtop lab technique, much like DMA, it was soon discovered that sensors could be developed for placement into a mold so the crosslinking process could be monitored in real time while manufacturing parts. This capability was demonstrated at NPE in 1991 at the booth of BMC Corp. Unfortunately, more than 30 years later, most thermoset molding processes still treat the mold like a black box where the curing process is invisible and mysterious, and nobody knows what is happening to the material until the mold opens.
This brings us to the topic of process control and the lack of sophistication in the thermoset industry in this endeavor when compared to thermoplastics. This difference in technology between the two branches of our industry is at least, in part, responsible for the minority status of thermosets. Once the dominant materials in our industry, crosslinked materials have been relegated to small market segments such as seals, O-rings, gaskets, some electrical components, composites and LSR parts for optical and medical device applications.
Yet there are real benefits to crosslinked materials that indicate they should be used more widely. In our next installment, we will look at the barriers that need to be overcome if thermosets are to regain some of the market share they have lost to thermoplastics over the last 75 years.
About the Author: Michael Sepe is an independent materials and processing consultant based in Sedona, Arizona, with clients throughout North America, Europe and Asia. He has more than 45 years of experience in the plastics industry and assists clients with material selection, designing for manufacturability, process optimization, troubleshooting and failure analysis. Contact: 928-203-0408 • mike@thematerialanalyst.com
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