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The texture profile analysis test is an imitative test to determine texture properties of food, which quantify the consumer’s perception of eating food. The instrumental texture parameters obtained from this test depend on the specimen size and the nonstandardized test conditions. To overcome this problem, texture properties are here related to intrinsic mechanical properties, which are independent of the test conditions. Two types of materials are used to investigate the effect of viscoelasticity, plasticity and damage on the texture parameters for varying test conditions. Analytical relations between mechanical properties, test conditions, and the instrumental hardness, springiness, cohesiveness, and adhesiveness are determined. The hardness is obtained from the stiffness of the material, which is potentially rate-dependent, and the yield stress of a material in case of plasticity. The springiness is determined by the recoverable or irrecoverable strain in the material, which results from the mechanical properties in combination with the test conditions. Cohesiveness and springiness are found to be strongly related, unless structural damage is present in the material. Adhesiveness is only an indirect measure of the adhesion between the material and compression plate and depends on the test conditions and stiffness of the material. Finite element simulations reveal a decrease of hardness in case of a nonflat top surface, indicating the importance of geometrical effects.

Pressure-sensitive adhesives (PSAs) are used in various industries, and have been widely applied in smart devices. In this study, the adhesion properties, viscoelastic properties, and gel fraction of PSAs were investigated after primary and secondary curing to understand their UV-curing behavior. In addition, the impact of concentration of crosslinking agent on the crosslinking density and the degree of crosslinking was investigated. In general, as more crosslinking agent was added, the hardness increased, but this result can be explained by the difference between “crosslinking density” and “degree of crosslinking” at the highest concentration of crosslinking agent actually led to a decrease in “degree of crosslinking”.

The development of solventless system for modulating properties of network materials is imperative for the next generation sustainable technology. Utilization of photostimulation is important owing to its spatial and temporal locality, yet designing photoresponsive network materials exhibiting repeatable and dramatic change in their properties remains a challenge. Here, the authors report a photocleavable regenerative network (PRN) linked with photoresponsive hexaarylbiimidazoles (HABIs) synthesized from narrow dispersity star‐shaped poly(dimethylsiloxane)s (PDMSs) having 2,4,5‐triphenylimidazole end groups. The use of urea anion as a catalyst for ring opening polymerization (ROP) of cyclic siloxane initiated from silanols enables control of molecular weight and dispersity. The rheological measurements for the synthesized PRNs exhibit drastic changes in storage and loss moduli (G′ and G″) upon photoirradiation in the solid state (G′ > G″). This photocontrolled change in viscoelasticity with retaining solidity enables application of PRNs as a remotely‐controlled photo‐melt adhesive and photo‐scissible string. The developed PRNs will enable a wide variety of applications such as industrially important next‐generation sustainable adhesive, sealant, and reversibly‐deformable 3D printing materials with their spatially and temporally local manipulability, solventless handleability, and excellent reversibility., Photocleavable regenerative networks (PRNs) are synthesized from structurally precise star‐shaped poly(dimethyl siloxane) precursors to realize a solventless spatially and temporally local dramatic change in mechanical properties. The photocontrolled dynamic change in viscoelasticity in the solid state enables application of PRNs as solventless remotely‐controlled photo‐melt adhesive and photo‐scissible string.