A method includes providing a gelant including a cross-linkable polymer, a crosslinking agent and an aqueous fluid, adding one or more fluorescent rare earth elements to the gelant to provide a fluorescent gelant solution in which a fluorescence emission is quenched, and initiating crosslinking of the gelant to form a gel by heating the fluorescent gelant solution. The intensity of the fluorescence emission of the fluorescent gelant solution is monitored as an indicator of gelation status and a gelation point of the gelant may be identified based on the intensity of the fluorescent emission of the fluorescent gelant solution.

Dental curing light systems capable of monitoring the degree of curing of polymerizable dental material. A monitoring light source delivers visible monitoring light at one or more different visible wavelengths and a visible light detector detects the monitoring light diffusely reflected by the polymerizable dental material. The monitoring light has a wavelength of maximum emission (max-mon) that does not effectively induce polymerization of the polymerizable dental material. Change in intensity of the monitoring light reflected from the polymerizable dental material is used to determine when a selected degree of curing is reached in the polymerizable dental material.

The present invention refers to the injectable hyaluronic acid composition which is crosslinked viscoelastic hyaluronic acid gel comprising DNA fractions. More particularly, it refers to the injectable hyaluronic acid composition comprising a hyaluronic acid composition crosslinked in the basic conditions with the degree of crosslinking between 0.1 and 200%, which is mixed with the DNA fractions of 0.1 to 50 wt %. The DNA fractions are selected, for example, from polynucleotide (PN) and polydeoxyribonucleotide (PDRN). The composition used for cosmetic purposes or therapeutic purposes, have improved viscoelastic rheological properties and enzyme resistance.

A method for determining an ultraviolet (UV) cure level of a material is disclosed. For example, the method includes receiving an object with the material that is cured via a UV light source, controlling a heat source to heat the material, measuring a parameter of the material in response to the heat, determining the UV cure level of the material based on the parameter that is measured and a predefined response of the material at a temperature associated with the heat, and generating a signal to display the UV cure level in response to the determining.

The present invention discloses a process for providing a cross-linked composition, the process comprising the steps of (a) providing an ethylene-?-olefin plastomer havinga density of from 850 kg/m.sup.3 to 900 kg/m.sup.3; andan melt flow rate (ISO 1133, 2.16 kg, 190? C.) of 0.3 to 50 g/10 min; (b) grafting the ethylene-?-olefin plastomer with silane crosslinker such that the content of silane crosslinker is in the range of 0.1 to 10.0 wt. % with respect to the grafted ethylene-?-olefin plastomer; (c) contacting said grafted ethylene-?-olefin plastomer with 2 to 8 wt. % of a tin-free silane crosslinking catalyst with respect to the resulting mixture of grafted ethylene-?-olefin plastomer and tin-freesilane crosslinking catalyst, wherein said tin-free catalyst comprises a Br?nsted acid at 23? C. and 50% relative humidity for at least 15 minutes thus forming a cross-linked composition, wherein gel content of said cross-linked composition after 15 min is at least 60%.

This disclosure provides a method for producing a cross-linked rubber for the additively fabricated object that can be easily produced with good dimensional accuracy and simplicity, even using a general-purpose uncross-linked rubber composition. This producing method is a method for producing a cross-linked rubber, in which an additively fabricated object of uncross-linked rubber is heated in a liquid to produce an additively fabricated object of cross-linked rubber, wherein the method includes, heating the additively fabricated object of uncross-linked rubber within the range not exceeding the saturated vapor pressure by controlling the temperature and pressure of the liquid, obtaining the equivalent cross-linking amounts at regular intervals from the start of heating using the following Formula (1), accumulating them and calculating the cumulative cross-linking degree, and stopping the cross-linking reaction when the cross-linking degree of the additively fabricated object of cross-linked rubber reaches the required cross-linking degree.

[00001]$\begin{array}{cc}U=\underset{i=1}{\overset{n}{.Math.}}\left\{e^{-\frac{E}{R}\left(\frac{1}{T}-\frac{1}{T_0}\right)}\right\}.Math.\left(\frac{t^i}{t_0}\right)& \left(1\right)\end{array}$

The invention relates to a method for controlling the stress distribution in a material, comprising the steps of: a, preparing a crosslinked polymer containing reversible exchange bonds; b, applying an external force to the crosslinked polymer to cause a certain strain; c, specific region of the crosslinked polymer is selectively heated while maintaining the strain. This method controls and utilizes the internal stresses which are commonly considered as unfavorable. The invention also provides a method for reading information in a polarized light field, wherein the crosslinked polymer treated by the method is transparent under natural light. The information therein can be read only under polarized light, and possesses concealment.

A method for determining an ultraviolet (UV) cure level of a material is disclosed. For example, the method includes receiving an object with the material that is cured via a UV light source, controlling a heat source to heat the material, measuring a parameter of the material in response to the heat, determining the UV cure level of the material based on the parameter that is measured and a predefined response of the material at a temperature associated with the heat, and generating a signal to display the UV cure level in response to the determining.

The present invention refers to the injectable hyaluronic acid composition which is crosslinked viscoelastic hyaluronic acid gel comprising DNA fractions. More particularly, it refers to the injectable hyaluronic acid composition comprising a hyaluronic acid composition crosslinked in the basic conditions with the degree of crosslinking between 0.1 and 200%, which is mixed with the DNA fractions of 0.1 to 50 wt %. The DNA fractions are selected, for example, from polynucleotide (PN) and polydeoxyribonucleotide (PDRN). The composition used for cosmetic purposes or therapeutic purposes, have improved viscoelastic rheological properties and enzyme resistance.

The present invention relates to an article consisting of or comprising a bidirectional shape-memory polymer (bSMP), the bSMP comprising: first phase-segregated domains (AD) having a first transition temperature (T.sub.t,AD) corresponding to a crystallization transition or glass transition of the first domains (AD), second phase-segregated domains (SD) having a second transition temperature (T.sub.t,SD) corresponding to a crystallization transition or glass transition of the second domains (SD), the second transition temperature (T.sub.t,SD) being higher than the first transition temperature (T.sub.t,AD), and covalent or physical bonds cross-linking the polymer chains of the bSMP, and in this way interconnecting the first and second domains (AD, SD), wherein the second phase-separated domains (SD) form a skeleton which is at least partially embedded in the first phase-segregated domains (AD), and wherein polymer chain segments of the bSMP forming the first domains (AD) are substantially orientated in a common direction, such that the bSMP is able to undergo a reversible shape-shift between a first shape (A) at a first temperature (T.sub.high) and a second shape (B) at a second temperature (T.sub.low) upon variation of temperature between the first and second temperature (T.sub.high, T.sub.low) driven by the crystallization and melting or vitrification and melting of the first phase-separated domains (AD) and without application of an external stress, with T.sub.low<T.sub.t,AD<T.sub.high<T.sub.t,SD.