Polyamide pre-expanded particles of this disclosure have a peak temperature of a maximum endothermic peak of 150-275° C. on a DSC curve obtained while being heated from 30° C. to 280° C. at a heating rate of 10° C./min using a DSC. The width of the peak is 30-80° C. when a straight line approximating the DSC curve on a high-temperature side relative to the peak after an end of melting is used as a baseline. The width corresponds to a difference between an extrapolated melting start temperature which is a temperature at an intersection point between a tangent line at an inflection point of the peak on a low-temperature side and the baseline, and an extrapolated melting end temperature which is a temperature at an intersection point between a tangent line at an inflection point of the peak on a high-temperature side and the baseline.

A process for the production of a geopolymer composite. The disclosure further relates to a geopolymer composite, and the use of a geopolymer, a geopolymer in combination with an athermanous additive, or the geopolymer composite in expanded vinyl polymer, preferably vinyl aromatic polymer. Furthermore, the disclosure relates to a process for the production of expandable vinyl aromatic polymer granulate, and expandable vinyl aromatic polymer granulate. Finally, the disclosure relates to expanded vinyl foam, preferably vinyl aromatic polymer, and to a masterbatch comprising vinyl polymer and a), b), or c).

A preparation method of a polyacrylonitrile-based three-dimensional macroporous carbon monolith. The process route of the method includes the following steps: completely dissolving polyacrylonitrile in an organic solvent, then carrying out drying, cutting, hot-pressing and punching to obtain a foam precursor, next, preparing a polyacrylonitrile foam with a controllable pore structure by a supercritical carbon dioxide batch foaming method, and finally carrying out pre-oxidation and carbonization treatment to obtain the polyacrylonitrile-based three-dimensional macroporous carbon monolith. The preparation method of the polyacrylonitrile-based three-dimensional macroporous carbon monolith of the present invention is simple, easy to control, environmentally friendly and low in cost, thus, the present invention is conducive to large-scale production of the carbon monolith. The prepared polyacrylonitrile-based three-dimensional macroporous carbon monolith has the characteristics of uniform and controllable pore structure and good conductivity, and has a broad application prospect. The method has simple steps, convenient operation and high practicability.

Expandable resin particles that have a reduced VOC content, a method of producing the expandable resin particles, and a foamed molded product that has reduced VOC emission are provided. The expandable resin particles contain a base material resin containing, as a structural unit, a styrene unit and an acrylonitrile unit and an expanding agent. The expandable resin particles have a styrene content and an ethylbenzene content each of which is not more than a specific amount.

Expanded particles of a polycarbonate-based resin containing a polycarbonate-based resin containing a component derived from bisphenol A as abase resin, the expanded particles being expanded particles of a polycarbonate-based resin satisfying any one of the following conditions (a) to (c) in a GC/MS chart: (a) a peak derived from a molecular weight of from 145 to 230 and a peak derived from a molecular weight of from 320 to 350 are shown; (b) a peak derived from a molecular weight of from 210 to 230 is shown; and (c) a peak derived from a molecular weight of from 290 to 320 is shown.

The invention relates to expandable polymer particles based on styrene polymers, to a process for the preparation thereof and to the use of the expandable polymer particles in a molded foam part. The polymer particles contain A) 87 to 99 wt. % of one or more styrene polymers (A), in relation to the total weight of (A), (B) and (C); B) 1 to 10 wt. % of one or more foaming agents (B); C) 0 to 3 wt. % of one or more nucleators or nucleating agents C); and optionally further additives (Z) in amounts which do not impair the domain formation and the foam structure resulting therefrom.

A method for producing polyamide-based resin multi-stage expanded beads includes an internal pressure applying step of placing polyamide-based resin expanded beads in a pressure-resistant container, impregnating the polyamide-based resin expanded beads with a physical blowing agent in the pressure-resistant container to apply internal pressure higher than atmospheric pressure; and a heating and foaming step of heating and expanding the polyamide-based resin expanded beads to which internal pressure is applied obtained in the internal pressure applying step to obtain polyamide-based resin multi-stage expanded beads having apparent density lower than that of polyamide-based resin expanded beads used in the internal pressure applying step, in the internal pressure applying step, polyamide-based resin expanded beads in a wet state having a water content of 1% or more being impregnated with the physical blowing agent at a temperature higher than change-point temperature of storage modulus of the polyamide-based resin expanded beads in a wet state.

The present invention relates to a process for the production of a geopolymer composite. It further relates to a geopolymer composite, and the use of a geopolymer, a geopolymer in combination with an athermanous additive, or the geopolymer composite in expanded vinyl polymer, preferably vinyl aromatic polymer. Furthermore, the invention relates to a process for the production of expandable vinyl aromatic polymer granulate, and expandable vinyl aromatic polymer granulate. Finally, the present invention relates to expanded vinyl foam, preferably vinyl aromatic polymer, and to a masterbatch comprising vinyl polymer and a), b), or c).

Pre-expanded polypropylene-based resin particles include a polypropylene-based resin. The polypropylene-based resin satisfies tan 0.32V+0.1, where tan represents a loss tangent at an angular frequency of 0.1 rad/s in dynamic viscoelastic behavior measurement at 200 C. and V represents a melt fracture take-up speed (m/min) at 200 C.

The invention relates to the use of a mineral having perovskite structure in vinyl aromatic polymer foam, i) for decreasing the thermal conductivity, ii) for increasing the mechanical properties (namely compressive strength and bending strength), or iii) for improving the self-extinguishing properties of the foam. The polymer foam further comprises one or more athermanous additives selected from a) powder inorganic additive selected from powders of silica and calcium phosphate, b) powder carbonaceous additive selected from powders of graphite, carbon black, petroleum coke, graphitized carbon black, graphite oxides, and graphene, and c) powder geopolymer and powder geopolymer composite.