PATENT CLAIM ANALYSIS

Application Number: 16078674
Application Type: Utility
Filing Date: 2018-08
Publication Date: 2019-02
Patent Classification: ["549", "274000"]

Abstract:
The present invention relates to a method for the catalytic synthesis of lactide from lactic acid. The method relates to the synthesis of lactide from lactic acid under the catalysis of a zinc oxide nanoparticle aqueous dispersion as a catalyst. The present invention has four technical characteristics: I. the zinc oxide nanoparticle aqueous dispersion catalyst has a sufficient surface area, and the size of nanoparticles is merely 30-40 nm, providing a sufficient contact area between the substrate (lactic acid) and the catalyst; II. the new catalyst has a milder catalytic effect on polymerization, allowing the molecular weight distribution of a prepolymer within a range of 400-1500 g/mol, which is advantageous for depolymerization to proceed; III. the new catalyst is stable, thus avoiding oxidation or carbonization in a high temperature reaction; and IV. the new catalyst has a low toxicity and a small threat to human health.

Claim (Index 3):
The method for the catalytic synthesis of lactide from lactic acid according to  claim 1 , characterized in that the method comprises the following steps:\n S 100 . Dehydration: lactic acid and a catalyst are mixed at a ratio under the conditions of 60-80\u00b0 C. and 60 kPa, and subjected to a dehydration reaction for 2 hours to remove free water from the lactic acid to obtain a dehydration product; S 200 . Polymerization: said dehydration product is subjected to a polymerization reaction for 3 hours under the conditions of 120-150\u00b0 C. and 10 kPa to obtain an oligomer; and S 300 . Depolymerization: said oligomer is subjected to a depolymerization reaction for 3-5 hours under the conditions of 170-220\u00b0 C. and 1-3 kPa.

Metadata:
- Claim Count in Document: 7.0
- Percentile: 96.0
- Lexical Diversity: 1.87356
- Patent Class: 549.0
- Transitional Phrase Type: none
- Component Type: 0
- Foreign Priority: True
- Related Applications: ['12809216', '13595627', '15290647', '14422526', '12563885']

Analysis Scores:
- 35 USC 101 Eligibility (BERT): 0.6993820001446914
- 35 USC 102 Novelty (BERT): 0.4937383139836844
- Combined Prediction Score: 0.6788176315285908
- Mean Citation Score: 205.514718
- Max Citation Score: 209.5321
- Similarity Product: 157.65825505210162

Labels:
- Claim Label 101: 1
- Claim Label 102: 1
- Claim Label 103: 0
- Claim Label 112: 1
- Combined Label: 1
- Label 101 Adjusted: 1

Dataset: test