Silly Putty Research Articles

Structure and impact properties of a thermoplastic elastomer/silly putty blend

AbstractThe structure and impact properties of a thermoplastic elastomer/silly putty blend are explored. The impact‐resistant materials are made with polyolefin‐based thermoplastic elastomer HYBRAR™ 5127 and silly putty DOWSIL™ 3179. The peak impact force decreases with the content of silly putty, as part of the impact energy might be dissipated by the dissociation of boron–oxygen dynamic dative bonds in silly putty. It is also observed that the crack behavior of samples under impact is related to the phase structure of silly putty in the samples. For the samples with high content of silly putty, a macroscopic crack is observed for these samples under impact, as a crack can spread in the continuous phase structure of silly putty. Different energy dissipation ratios in rheological, compression and impact experiments are also observed. It is concluded that the results of linear dynamic oscillatory shear and compression at a low strain rate cannot give a direct predication of energy dissipation ratios of samples under impact at a high strain rate. © 2021 Society of Industrial Chemistry.

Extrusion rheometry of collagen dough

Although collagen is widely used (for example, in the food industry, in the pharmaceutical industry and in biomedicine), the rheological properties of the material are not well known for high concentrations (8% collagen, 90% water). Rheological properties were measured using a capillary-slit rheometer (an extrusion process), where the tested sample of collagen matter was pushed by a hydraulically driven piston through a narrow rectangular slit at very high shear rates of 50–6 000 s<sup>–1</sup>. The Herschel-Bulkley (HB) constitutive equation and a new correlation taking into account the finite gap width was used to evaluate the rheological properties (n = 0.2, K = 879 Pa s<sup>n</sup>, τ<sub>0</sub> = 2 380 Pa). Use was made of a new yield stress measurement method evaluating τ<sub>0</sub> 'post mortem' after extrusion stops. The effects of wall slip and of air bubbles, which caused apparent compressibility of the 'silly putty' collagen material, were also studied. Corrections of the wall slip effect were implemented using sliding layer thickness δ.

The Normal Force Characteristic of a Novel Magnetorheological Elastomer Based on Butadiene Rubber Matrix Compounded with the Self‐Fabricated Silly Putty

In this paper, a novel magnetorheological elastomer (MRE) was prepared by dispersing carbonyl iron particles (CIPs) into a composite matrix compounded by butadiene rubber (BR) and self‐fabricated Silly Putty. The rate‐sensitive and magneto‐induced characteristics of normal force were experimental investigated to discuss the working mechanism. The results demonstrated that the normal force increased with the compression rate and the mass fraction of boron‐silicon copolymer added to the composite matrix due to the formation of the more and more B‐O cross bonds which could be blocked in the C‐C cross‐linked network of BR. Meanwhile, the magneto‐induced normal force was positively correlated with the applied magnetic field strength and the compression strain due to the decreased gap between the centers of soft magnetic particles and the increased particle intensity of magnetization. Moreover, the magneto‐induced normal force continued to enhance with the increase of compression strain because the CIP chains fixed in the C‐C cross‐linked network could bend to a radian and CIP chains in B‐O cross‐linked network could rupture to form more stable and intensive short‐chain structures. Besides, a simplified model was deduced to characterize the mechanism of the generation of the magneto‐induced normal force. Furthermore, the normal force varied stably with the oscillatory shear strain (less than 9%) at different magnetic induction intensities and suddenly reduced when the applied oscillatory shear strain was more than 9%.

Mapping linear viscoelasticity for design and tactile intuition

AbstractWe propose and study methods to improve tactile intuition for linear viscoelastic fluids. This includes (i) Pipkin mapping with amplitude based on stress rather than strain or strain-rate to map perception to rheological test conditions; and (ii) data reduction of linear viscoelastic functions to generate multi-dimensional Ashby-style cross-property plots. Two model materials are used, specifically chosen to be easily accessible and safe to handle, with variable elastic, viscous, and relaxation time distributions. First, a commercially available polymer melt known as physical therapy putty, reminiscent of Silly Putty, designed for a range of user experiences (extra-soft to extra-firm). Second, a transiently cross-linked aqueous polymer solution (Polyvinyl alcohol-Sodium Tetraborate, PVA-Borax). Readers are encouraged to procure or produce the samples themselves to build intuition. The methods studied here reduce the complexity of the function-valued viscoelastic data, identifying what key features we sense and see when handling these materials, and provide a framework for tactile intuition, material selection, and material design for linear viscoelastic fluids generally.

The Mechanical Properties of a Novel STMR Damper Based on Magnetorheological Silly Putty

A novel shear thickening magnetorheological (STMR) damper with both speed locking and semiactive controlling properties was designed and fabricated based on multifunctional smart composite materials which was defined as magnetorheological Silly Putty (MRSP). The rate sensitive property and magnetorheological effect of MRSP samples were analyzed by using a rheometer to select the best filler for the STMR damper. The mechanical properties of the STMR damper were investigated through slow, fast, and dynamic experiments. The experimental results indicate that the STMR damper exhibits an obvious rate sensitive characteristic and semiactive control property. On one hand, when the STMR damper is simulated fast enough, it can realize the “speed switch” function, which enables it to instantly lock up and act as a shock transmission unit (STU). On the other hand, when the STMR damper is applied with current, the damping force can be adjusted by magnetic field strength to realize its semiactive controlling property. In addition, a multiparameter and symmetry model was established to describe the dynamic hysteretic behavior of the STMR damper, which is consistent with the experimental data.

Anti-impact response of Kevlar sandwich structure with silly putty core

A soft sandwich structure consisting of two layer Kevlar face sheets and a silly putty (SP) core was fabricated. The storage modulus of SP, which was prepared by dispersing CaCO3 particles into polyborodimethylsiloxane, increased by two to three orders of magnitude with increasing of the shear frequency. The higher CaCO3 content resulted in better shear-hardening behavior, which further enhanced the anti-impact performance of the sandwich structure. When the impact velocity was below 110 m/s, all energy was dissipated by the sandwich structure and the maximum energy dissipation was 20.8 J, represented a 60% increment than the neat Kevlar. Importantly, under the same impact energy, the energy dissipation of the sandwich structure under ballistic impact was 63% higher than under low velocity impact, which must be due to the shear-hardening nature. The mechanism of the excellent protection performance was discussed. The sensitivity to loading rate and reliable energy dissipation of the soft sandwich structure widely broad its practical applications.

Graphene-spiked Silly Putty picks up human pulse

Graphene-spiked Silly Putty picks up human pulse

Supercharged silly putty can detect spider footsteps

Supercharged silly putty can detect spider footsteps

The Static and Dynamic Mechanical Properties of Magnetorheological Silly Putty

A novel magnetorheological material defined as magnetorheological Silly Putty (MRSP) is prepared by dispersing soft magnetic particles into Silly Putty matrix with shear stiffening property. Static mechanical properties including creep and stress relaxation and dynamic rheological properties of MRSPs are tested by rheometer. The experimental results indicate that the external magnetic field exerts significant influence on the creep and relaxation behaviors. Moreover, the storage modulus of MRSPs increases sharply in response to the external stimuli of increasing angular frequency automatically and can be enhanced by external magnetic field. Besides, temperature plays a key role in shear stiffening and magnetorheological effect of MRSPs. Furthermore, considering the obstruction to the particle chains formation induced by Silly Putty matrix, a nonperforative particle aggregated chains model is proposed. The model curve is in consistency with experimental data, which means it can describe magnetoinduced behavior of MRSPs well.

Mechanical behaviour of magnetic Silly Putty: Viscoelastic and magnetorheological properties

In this work the mechanical and viscoelastic properties of magnetic Silly Putty are investigated. Silly Putty is a non-Newtonian material whose response depends on the rate at which it is deformed. For a rapid deformation, it behaves as an elastic solid, while over a relatively long time scale, the polymer molecules can be untangled and it flows as a fluid. The purpose of this article is to study the behaviour of this material firstly under a quasi-static compression and shear loading, and secondly under dynamic shear loading. The Silly Putty under study has a volume fraction of ferromagnetic particles. Hence, both quasi-static and dynamic stress are coupled with several strengths of magnetic field in order to assess the influence of the magnetisation on the mechanical and viscoelastic properties of the material. The approach adopted in this work followed the Design of Experiment method so that evaluating the influence of the variables and their interactions on the system response is possible. The results highlight a strong dependence on the deformation rate, while the influence of the magnetic field is weak, especially under dynamic shear tests in which the viscous components are predominant.

Rheological Properties of SP in Shock Transmission Application

AbstractThe rheological properties of silly putty (SP) and its application as a shock transmission unit (STU) were studied in the paper. By using a parallel-plate rheometer, the frequency sweep at different temperature was carried out to investigate the rheological properties of SP. For all test temperatures, the complex viscosity of SP shows shear thinning, but the G′-curve shows a moderate slope and a gradual transition to the constant plateau value. And once the angular frequency exceeds a critical value, the storage modulus will exceed the loss modulus under the condition of all temperatures. Two prototypes of STU were fabricated with SP and their mechanical performances were experimentally evaluated. The results of the slow movement test and the simulated dynamic test show that the STU can provide a free motion under slowly applied loads and a rigid link under impact loads.

Analysis and Research on Construction Technology of Air Return Inclined Shaft Crossing Formation on Special Conditions

The sectional area of air return inclined shaft 1 in Hecaogou coal mine is 20.7m2 and the dip angle is 20°. It belongs to the large angle and section inclined shaft. The soil of mining area has the characteristics of loose, poor stability and integrity, low compressive strength, easy to be in the rheological and pulverization. After the first support in hidden digging section of air return inclined shaft 1, the soft and collapsible loess strata turned into the shape of silly putty because of the construction disturbance, which caused serious deformation and subsidence to that shaft. We succeed to pass the extra thick soft and collapsible loess strata and obtain the expected effect the by means of analyzing deformation principle of surrounding rock on shaft and grouting reinforcement of rail pile and advanced support of exploration of thread steel and metal wedge and comprehensive technology of using stone to take the place of the floor loess. It has reference significance to the other shaft and drift construction with the similar formation condition

Nonlinearity of a Voltage-Gated Potassium Channel Revealed by the Mechanical Susceptibility

Voltage-gated ion channels regulate the flows of sodium or potassium ions across nerve cell membranes. A new study of a model potassium channel reveals that behind the channel's regulation of the ion flow lies a viscoelastic molecular structural behavior similar to that of Silly Putty.

Elastic Properties of Plasticine, Silly Putty, and Tennis Strings

How would a physicist describe the elastic properties of an apple or a banana? Physics students and teachers are familiar with the elastic properties of metal springs, but are likely to be less familiar with the elastic properties of other common materials. The behavior of a metal spring is commonly examined in the laboratory by adding masses to measure the change in the extension or compression. A banana or an apple or any other relatively soft material could just as easily be examined in the same way, as an additional and entertaining exercise. Even if an apparatus is not readily available to undertake such an experiment, it can easily be constructed.1,2 In this article I compare the elastic properties of Plasticine (a brand of modeling clay), Silly Putty, and tennis strings. All three materials behave in the same qualitative manner when stretched or compressed slowly, despite the fact that they are quite different when stretched or compressed rapidly and despite the fact that Plasticine and Silly Putty are both much softer than a tennis string. Typical results for a slow deformation are shown in Fig. 1.

Elastic and viscous properties of Silly Putty

We consider in this paper the elastic and viscous properties of Silly Putty and confirm the well known fact that the properties depend on the rate at which the material is deformed. Rapid deformations were studied by dropping masses onto one end of a Silly Putty cylinder, and slow deformations were studied by compressing the cylinder in a materials testing machine. The results were compared with a simple engineering model of viscoelastic materials to estimate the stiffness and the viscosity of the Silly Putty cylinder. It was found that stress induced in Silly Putty relaxes with a time constant of about 0.1 s, Young’s modulus for a rapid deformation is about 1.7 × 106 N/m2, and the viscosity for a slow compression is about 8 × 104 Pa s. When subject to a short impact, Silly Putty vibrates as a result of compressional wave propagation through the material.

Laboratory Activity: Specific Heat by Change in Internal Energy of Silly Putty

Students in introductory physics courses often don't study thermodynamics or thermodynamic events. If any thermal physics is taught in introductory courses (e.g., Physics 101 for Liberal Arts Majors), it usually involves the concepts of specific heat and various temperature scales. Seldom are the first and second laws of thermodynamics taught in detail. In this article, we look at a means to obtain real-time data that will lead to clarifying the first law.

The Centrality of Theoretical Thinking and the Value of Empirical Evidence

On a recent balmy summer day, while scholarly work sat in a briefcase with ever-accessible laptop computer, I was playfully engaged with 5-year-old grandson Elliot on the porch of our summer home overlooking Lake Erie. With the Marblehead lighthouse and Cedar Point Amusement Park visible in the distance, we were occupying our time with the contents of a freshly opened container of a modeling compound. While both of us were well acquainted with the properties of modeling clay, Play-Doh, and Silly Putty, neither had prior experience with this particular medium. It was composed of a pink gelatinous-looking material and zillions of tiny white foam beads. Taking a handful and attempting to form it into a shape, Elliot remarked that it was too crumbly. When I attempted to shape the compound myself, I too noticed that it wasn't hanging together very well. Elliot posed, what's your theory about this stuff not sticking together? As a theorist and teacher of nursing theory, I was a little surprised and more than gleeful that, at age 5, grandson even had the word theory in his vocabulary. Then I began to wonder what the word meant to him, particularly as graduate nursing students often seemed to have some innate aversion to the term. Buying time and plying the material in hand, I said pensively, Hmmm, theory. (pause) I'll have to think about Immersing himself in thought, Elliot stared at the crumbs of gel and beads scattered across the tabletop, fingered them gingerly, and began offering his ideas freely: maybe the stuff was too old, maybe there were too many beads for the amount of goo, maybe there was something wrong with the goo, maybe the beads had soaked up the sticky from the goo, maybe our hands were too dry. I listened raptly as he generated and explained each idea, interjecting an occasional Hmmm or shrug to encourage him on. I was fascinated by his thinking, the experiences he drew from, the notions he connected, and the reasons he offered to support each plausible explanation. I was impressed with the extent of his knowledge and his creativity in applying it. I struggled to listen and to keep it all in head at the same time as I also attempted to analyze what he was actually doing. Theorizing. He was indeed theorizing. It was all there: a phenomenon, concepts, relational statements, assumptions, a worldview. My grandson was an armchair theorist. At a fundamental level, he had a firm grasp of the meaning of the word theory. Finally, exasperated by silence, feeling unsure about which of his theories was correct or true, and unsatisfied that he had no solution to his practical problem, he exclaimed, Grandma, what is your theory? Well, I said, holding out to his receptive fingers a warm, pliable homogeneous mass of the stuff, my theory is that the goo had to be warmer to stick together and to the balls. …

Temperature dependent relaxation of a “solid–liquid”

AbstractWe have used the Interfacial Force Microscope to perform temperature dependent indentation measurements on a model viscoelastic material, Silly Putty. By transforming time dependent stress relaxations into frequency dependent modulus, we can identify the temperature dependence of the elastic and viscous response of an experimentally challenging material. This technique promises to be useful in determining the mechanical properties of composite materials with microscopic spatial resolution. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1285–1290, 2009

Failure Notice

Failure Notice

Making silly putty

Change is the theme is the focus of this month's experiment, with children encouraged to make their own silly putty