The softening temperature of acrylic sheet (polymethyl methacrylate) is not a fixed point, but has a certain range. Generally speaking, the softening temperature of acrylic can be between 99 ℃ and 105 ℃, but the specific values may vary depending on the production process, material formula, and testing conditions.

In addition, the heat resistance of acrylic is also related to its continuous working temperature range. Under normal circumstances, acrylic products will not deform or break due to heat resistance, but the size of acrylic sheets may change to some extent when exposed to high temperatures for a long time. Generally speaking, the temperature range that acrylic sheets can withstand is between -40 ℃ and+104 ℃, while the temperature range for continuous operation may be between 65 ℃ and 95 ℃.

It is worth noting that the thermal deformation temperature and Vicat softening point of acrylic are important indicators for evaluating its heat resistance performance. The hot deformation temperature refers to the temperature at which a material undergoes a certain deformation under a certain pressure, while the Vicat softening point is the temperature at which the material begins to soften during the heating process. For acrylic, its thermal deformation temperature is about 96 ℃ (under a pressure of 1.18MPa), while the Vicat softening point may reach 113 ℃.

In summary, acrylic sheets may begin to soften when they approach or exceed their softening temperature, but the specific temperature may vary due to various factors. When using acrylic sheets, appropriate materials and designs should be selected based on specific working conditions and requirements to ensure the stability and safety of their performance.